--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/test/test-fs.c	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,4922 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "task.h"
+
+#include <errno.h>
+#include <string.h> /* memset */
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <limits.h> /* INT_MAX, PATH_MAX, IOV_MAX */
+
+#ifndef _WIN32
+# include <unistd.h> /* unlink, rmdir, etc. */
+#else
+# include <winioctl.h>
+# include <direct.h>
+# include <io.h>
+# ifndef ERROR_SYMLINK_NOT_SUPPORTED
+#  define ERROR_SYMLINK_NOT_SUPPORTED 1464
+# endif
+# ifndef S_IFIFO
+#  define S_IFIFO _S_IFIFO
+# endif
+# define unlink _unlink
+# define rmdir _rmdir
+# define open _open
+# define write _write
+# define close _close
+# ifndef stat
+#  define stat _stati64
+# endif
+# ifndef lseek
+#   define lseek _lseek
+# endif
+# define S_IFDIR _S_IFDIR
+# define S_IFCHR _S_IFCHR
+# define S_IFREG _S_IFREG
+#endif
+
+#define TOO_LONG_NAME_LENGTH 65536
+#define PATHMAX 4096
+
+#ifdef _WIN32
+static const int is_win32 = 1;
+#else
+static const int is_win32 = 0;
+#endif
+
+#if defined(__APPLE__) || defined(__SUNPRO_C)
+static const int is_apple_or_sunpro_c = 1;
+#else
+static const int is_apple_or_sunpro_c = 0;
+#endif
+
+typedef struct {
+  const char* path;
+  double atime;
+  double mtime;
+} utime_check_t;
+
+
+static int dummy_cb_count;
+static int close_cb_count;
+static int create_cb_count;
+static int open_cb_count;
+static int read_cb_count;
+static int write_cb_count;
+static int unlink_cb_count;
+static int mkdir_cb_count;
+static int mkdtemp_cb_count;
+static int mkstemp_cb_count;
+static int rmdir_cb_count;
+static int scandir_cb_count;
+static int stat_cb_count;
+static int rename_cb_count;
+static int fsync_cb_count;
+static int fdatasync_cb_count;
+static int ftruncate_cb_count;
+static int sendfile_cb_count;
+static int fstat_cb_count;
+static int access_cb_count;
+static int chmod_cb_count;
+static int fchmod_cb_count;
+static int chown_cb_count;
+static int fchown_cb_count;
+static int lchown_cb_count;
+static int link_cb_count;
+static int symlink_cb_count;
+static int readlink_cb_count;
+static int realpath_cb_count;
+static int utime_cb_count;
+static int futime_cb_count;
+static int lutime_cb_count;
+static int statfs_cb_count;
+
+static uv_loop_t* loop;
+
+static uv_fs_t open_req1;
+static uv_fs_t open_req2;
+static uv_fs_t open_req_noclose;
+static uv_fs_t read_req;
+static uv_fs_t write_req;
+static uv_fs_t unlink_req;
+static uv_fs_t close_req;
+static uv_fs_t mkdir_req;
+static uv_fs_t mkdtemp_req1;
+static uv_fs_t mkdtemp_req2;
+static uv_fs_t mkstemp_req1;
+static uv_fs_t mkstemp_req2;
+static uv_fs_t mkstemp_req3;
+static uv_fs_t rmdir_req;
+static uv_fs_t scandir_req;
+static uv_fs_t stat_req;
+static uv_fs_t rename_req;
+static uv_fs_t fsync_req;
+static uv_fs_t fdatasync_req;
+static uv_fs_t ftruncate_req;
+static uv_fs_t sendfile_req;
+static uv_fs_t utime_req;
+static uv_fs_t futime_req;
+
+static char buf[32];
+static char buf2[32];
+static char test_buf[] = "test-buffer\n";
+static char test_buf2[] = "second-buffer\n";
+static uv_buf_t iov;
+
+#ifdef _WIN32
+int uv_test_getiovmax(void) {
+  return INT32_MAX; /* Emulated by libuv, so no real limit. */
+}
+#else
+int uv_test_getiovmax(void) {
+#if defined(IOV_MAX)
+  return IOV_MAX;
+#elif defined(_SC_IOV_MAX)
+  static int iovmax = -1;
+  if (iovmax == -1) {
+    iovmax = sysconf(_SC_IOV_MAX);
+    /* On some embedded devices (arm-linux-uclibc based ip camera),
+     * sysconf(_SC_IOV_MAX) can not get the correct value. The return
+     * value is -1 and the errno is EINPROGRESS. Degrade the value to 1.
+     */
+    if (iovmax == -1) iovmax = 1;
+  }
+  return iovmax;
+#else
+  return 1024;
+#endif
+}
+#endif
+
+#ifdef _WIN32
+/*
+ * This tag and guid have no special meaning, and don't conflict with
+ * reserved ids.
+*/
+static unsigned REPARSE_TAG = 0x9913;
+static GUID REPARSE_GUID = {
+  0x1bf6205f, 0x46ae, 0x4527,
+  { 0xb1, 0x0c, 0xc5, 0x09, 0xb7, 0x55, 0x22, 0x80 }};
+#endif
+
+static void check_permission(const char* filename, unsigned int mode) {
+  int r;
+  uv_fs_t req;
+  uv_stat_t* s;
+
+  r = uv_fs_stat(NULL, &req, filename, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+
+  s = &req.statbuf;
+#if defined(_WIN32) || defined(__CYGWIN__) || defined(__MSYS__)
+  /*
+   * On Windows, chmod can only modify S_IWUSR (_S_IWRITE) bit,
+   * so only testing for the specified flags.
+   */
+  ASSERT((s->st_mode & 0777) & mode);
+#else
+  ASSERT((s->st_mode & 0777) == mode);
+#endif
+
+  uv_fs_req_cleanup(&req);
+}
+
+
+static void dummy_cb(uv_fs_t* req) {
+  (void) req;
+  dummy_cb_count++;
+}
+
+
+static void link_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_LINK);
+  ASSERT_OK(req->result);
+  link_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void symlink_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_SYMLINK);
+  ASSERT_OK(req->result);
+  symlink_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void readlink_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_READLINK);
+  ASSERT_OK(req->result);
+  ASSERT_OK(strcmp(req->ptr, "test_file_symlink2"));
+  readlink_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void realpath_cb(uv_fs_t* req) {
+  char test_file_abs_buf[PATHMAX];
+  size_t test_file_abs_size = sizeof(test_file_abs_buf);
+  ASSERT_EQ(req->fs_type, UV_FS_REALPATH);
+  ASSERT_OK(req->result);
+
+  uv_cwd(test_file_abs_buf, &test_file_abs_size);
+#ifdef _WIN32
+  strcat(test_file_abs_buf, "\\test_file");
+  ASSERT_OK(_stricmp(req->ptr, test_file_abs_buf));
+#else
+  strcat(test_file_abs_buf, "/test_file");
+  ASSERT_OK(strcmp(req->ptr, test_file_abs_buf));
+#endif
+  realpath_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void access_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_ACCESS);
+  access_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void fchmod_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_FCHMOD);
+  ASSERT_OK(req->result);
+  fchmod_cb_count++;
+  uv_fs_req_cleanup(req);
+  check_permission("test_file", *(int*)req->data);
+}
+
+
+static void chmod_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_CHMOD);
+  ASSERT_OK(req->result);
+  chmod_cb_count++;
+  uv_fs_req_cleanup(req);
+  check_permission("test_file", *(int*)req->data);
+}
+
+
+static void fchown_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_FCHOWN);
+  ASSERT_OK(req->result);
+  fchown_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void chown_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_CHOWN);
+  ASSERT_OK(req->result);
+  chown_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void lchown_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_LCHOWN);
+  ASSERT_OK(req->result);
+  lchown_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void chown_root_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_CHOWN);
+#if defined(_WIN32) || defined(__MSYS__)
+  /* On windows, chown is a no-op and always succeeds. */
+  ASSERT_OK(req->result);
+#else
+  /* On unix, chown'ing the root directory is not allowed -
+   * unless you're root, of course.
+   */
+  if (geteuid() == 0)
+    ASSERT_OK(req->result);
+  else
+#   if defined(__CYGWIN__)
+    /* On Cygwin, uid 0 is invalid (no root). */
+    ASSERT_EQ(req->result, UV_EINVAL);
+#   elif defined(__PASE__)
+    /* On IBMi PASE, there is no root user. uid 0 is user qsecofr.
+     * User may grant qsecofr's privileges, including changing
+     * the file's ownership to uid 0.
+     */
+    ASSERT(req->result == 0 || req->result == UV_EPERM);
+#   else
+    ASSERT_EQ(req->result, UV_EPERM);
+#   endif
+#endif
+  chown_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void unlink_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &unlink_req);
+  ASSERT_EQ(req->fs_type, UV_FS_UNLINK);
+  ASSERT_OK(req->result);
+  unlink_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void fstat_cb(uv_fs_t* req) {
+  uv_stat_t* s = req->ptr;
+  ASSERT_EQ(req->fs_type, UV_FS_FSTAT);
+  ASSERT_OK(req->result);
+  ASSERT_EQ(s->st_size, sizeof(test_buf));
+  uv_fs_req_cleanup(req);
+  fstat_cb_count++;
+}
+
+
+static void statfs_cb(uv_fs_t* req) {
+  uv_statfs_t* stats;
+
+  ASSERT_EQ(req->fs_type, UV_FS_STATFS);
+  ASSERT_OK(req->result);
+  ASSERT_NOT_NULL(req->ptr);
+  stats = req->ptr;
+
+#if defined(_WIN32) || defined(__sun) || defined(_AIX) || defined(__MVS__) || \
+  defined(__OpenBSD__) || defined(__NetBSD__)
+  ASSERT_OK(stats->f_type);
+#else
+  ASSERT_UINT64_GT(stats->f_type, 0);
+#endif
+
+  ASSERT_GT(stats->f_bsize, 0);
+  ASSERT_GT(stats->f_blocks, 0);
+  ASSERT_LE(stats->f_bfree, stats->f_blocks);
+  ASSERT_LE(stats->f_bavail, stats->f_bfree);
+
+#ifdef _WIN32
+  ASSERT_OK(stats->f_files);
+  ASSERT_OK(stats->f_ffree);
+#else
+  /* There is no assertion for stats->f_files that makes sense, so ignore it. */
+  ASSERT_LE(stats->f_ffree, stats->f_files);
+#endif
+  uv_fs_req_cleanup(req);
+  ASSERT_NULL(req->ptr);
+  statfs_cb_count++;
+}
+
+
+static void close_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &close_req);
+  ASSERT_EQ(req->fs_type, UV_FS_CLOSE);
+  ASSERT_OK(req->result);
+  close_cb_count++;
+  uv_fs_req_cleanup(req);
+  if (close_cb_count == 3) {
+    r = uv_fs_unlink(loop, &unlink_req, "test_file2", unlink_cb);
+    ASSERT_OK(r);
+  }
+}
+
+
+static void ftruncate_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &ftruncate_req);
+  ASSERT_EQ(req->fs_type, UV_FS_FTRUNCATE);
+  ASSERT_OK(req->result);
+  ftruncate_cb_count++;
+  uv_fs_req_cleanup(req);
+  r = uv_fs_close(loop, &close_req, open_req1.result, close_cb);
+  ASSERT_OK(r);
+}
+
+static void fail_cb(uv_fs_t* req) {
+  FATAL("fail_cb should not have been called");
+}
+
+static void read_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &read_req);
+  ASSERT_EQ(req->fs_type, UV_FS_READ);
+  ASSERT_GE(req->result, 0);  /* FIXME(bnoordhuis) Check if requested size? */
+  read_cb_count++;
+  uv_fs_req_cleanup(req);
+  if (read_cb_count == 1) {
+    ASSERT_OK(strcmp(buf, test_buf));
+    r = uv_fs_ftruncate(loop, &ftruncate_req, open_req1.result, 7,
+        ftruncate_cb);
+  } else {
+    ASSERT_OK(strcmp(buf, "test-bu"));
+    r = uv_fs_close(loop, &close_req, open_req1.result, close_cb);
+  }
+  ASSERT_OK(r);
+}
+
+
+static void open_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &open_req1);
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  if (req->result < 0) {
+    fprintf(stderr, "async open error: %d\n", (int) req->result);
+    ASSERT(0);
+  }
+  open_cb_count++;
+  ASSERT(req->path);
+  ASSERT_OK(memcmp(req->path, "test_file2\0", 11));
+  uv_fs_req_cleanup(req);
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(loop, &read_req, open_req1.result, &iov, 1, -1,
+      read_cb);
+  ASSERT_OK(r);
+}
+
+
+static void open_cb_simple(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  if (req->result < 0) {
+    fprintf(stderr, "async open error: %d\n", (int) req->result);
+    ASSERT(0);
+  }
+  open_cb_count++;
+  ASSERT(req->path);
+  uv_fs_req_cleanup(req);
+}
+
+
+static void fsync_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &fsync_req);
+  ASSERT_EQ(req->fs_type, UV_FS_FSYNC);
+  ASSERT_OK(req->result);
+  fsync_cb_count++;
+  uv_fs_req_cleanup(req);
+  r = uv_fs_close(loop, &close_req, open_req1.result, close_cb);
+  ASSERT_OK(r);
+}
+
+
+static void fdatasync_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &fdatasync_req);
+  ASSERT_EQ(req->fs_type, UV_FS_FDATASYNC);
+  ASSERT_OK(req->result);
+  fdatasync_cb_count++;
+  uv_fs_req_cleanup(req);
+  r = uv_fs_fsync(loop, &fsync_req, open_req1.result, fsync_cb);
+  ASSERT_OK(r);
+}
+
+
+static void write_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &write_req);
+  ASSERT_EQ(req->fs_type, UV_FS_WRITE);
+  ASSERT_GE(req->result, 0);  /* FIXME(bnoordhuis) Check if requested size? */
+  write_cb_count++;
+  uv_fs_req_cleanup(req);
+  r = uv_fs_fdatasync(loop, &fdatasync_req, open_req1.result, fdatasync_cb);
+  ASSERT_OK(r);
+}
+
+
+static void create_cb(uv_fs_t* req) {
+  int r;
+  ASSERT_PTR_EQ(req, &open_req1);
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  ASSERT_GE(req->result, 0);
+  create_cb_count++;
+  uv_fs_req_cleanup(req);
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(loop, &write_req, req->result, &iov, 1, -1, write_cb);
+  ASSERT_OK(r);
+}
+
+
+static void rename_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &rename_req);
+  ASSERT_EQ(req->fs_type, UV_FS_RENAME);
+  ASSERT_OK(req->result);
+  rename_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void mkdir_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &mkdir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_MKDIR);
+  ASSERT_OK(req->result);
+  mkdir_cb_count++;
+  ASSERT(req->path);
+  ASSERT_OK(memcmp(req->path, "test_dir\0", 9));
+  uv_fs_req_cleanup(req);
+}
+
+
+static void check_mkdtemp_result(uv_fs_t* req) {
+  int r;
+
+  ASSERT_EQ(req->fs_type, UV_FS_MKDTEMP);
+  ASSERT_OK(req->result);
+  ASSERT(req->path);
+  ASSERT_EQ(15, strlen(req->path));
+  ASSERT_OK(memcmp(req->path, "test_dir_", 9));
+  ASSERT_NE(0, memcmp(req->path + 9, "XXXXXX", 6));
+  check_permission(req->path, 0700);
+
+  /* Check if req->path is actually a directory */
+  r = uv_fs_stat(NULL, &stat_req, req->path, NULL);
+  ASSERT_OK(r);
+  ASSERT(((uv_stat_t*)stat_req.ptr)->st_mode & S_IFDIR);
+  uv_fs_req_cleanup(&stat_req);
+}
+
+
+static void mkdtemp_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &mkdtemp_req1);
+  check_mkdtemp_result(req);
+  mkdtemp_cb_count++;
+}
+
+
+static void check_mkstemp_result(uv_fs_t* req) {
+  int r;
+
+  ASSERT_EQ(req->fs_type, UV_FS_MKSTEMP);
+  ASSERT_GE(req->result, 0);
+  ASSERT(req->path);
+  ASSERT_EQ(16, strlen(req->path));
+  ASSERT_OK(memcmp(req->path, "test_file_", 10));
+  ASSERT_NE(0, memcmp(req->path + 10, "XXXXXX", 6));
+  check_permission(req->path, 0600);
+
+  /* Check if req->path is actually a file */
+  r = uv_fs_stat(NULL, &stat_req, req->path, NULL);
+  ASSERT_OK(r);
+  ASSERT(stat_req.statbuf.st_mode & S_IFREG);
+  uv_fs_req_cleanup(&stat_req);
+}
+
+
+static void mkstemp_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &mkstemp_req1);
+  check_mkstemp_result(req);
+  mkstemp_cb_count++;
+}
+
+
+static void rmdir_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &rmdir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_RMDIR);
+  ASSERT_OK(req->result);
+  rmdir_cb_count++;
+  ASSERT(req->path);
+  ASSERT_OK(memcmp(req->path, "test_dir\0", 9));
+  uv_fs_req_cleanup(req);
+}
+
+
+static void assert_is_file_type(uv_dirent_t dent) {
+#ifdef HAVE_DIRENT_TYPES
+  /*
+   * For Apple and Windows, we know getdents is expected to work but for other
+   * environments, the filesystem dictates whether or not getdents supports
+   * returning the file type.
+   *
+   *   See:
+   *     http://man7.org/linux/man-pages/man2/getdents.2.html
+   *     https://github.com/libuv/libuv/issues/501
+   */
+  #if defined(__APPLE__) || defined(_WIN32)
+    ASSERT_EQ(dent.type, UV_DIRENT_FILE);
+  #else
+    ASSERT(dent.type == UV_DIRENT_FILE || dent.type == UV_DIRENT_UNKNOWN);
+  #endif
+#else
+  ASSERT_EQ(dent.type, UV_DIRENT_UNKNOWN);
+#endif
+}
+
+
+static void scandir_cb(uv_fs_t* req) {
+  uv_dirent_t dent;
+  ASSERT_PTR_EQ(req, &scandir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SCANDIR);
+  ASSERT_EQ(2, req->result);
+  ASSERT(req->ptr);
+
+  while (UV_EOF != uv_fs_scandir_next(req, &dent)) {
+    ASSERT(strcmp(dent.name, "file1") == 0 || strcmp(dent.name, "file2") == 0);
+    assert_is_file_type(dent);
+  }
+  scandir_cb_count++;
+  ASSERT(req->path);
+  ASSERT_OK(memcmp(req->path, "test_dir\0", 9));
+  uv_fs_req_cleanup(req);
+  ASSERT(!req->ptr);
+}
+
+
+static void empty_scandir_cb(uv_fs_t* req) {
+  uv_dirent_t dent;
+
+  ASSERT_PTR_EQ(req, &scandir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SCANDIR);
+  ASSERT_OK(req->result);
+  ASSERT_NULL(req->ptr);
+  ASSERT_EQ(UV_EOF, uv_fs_scandir_next(req, &dent));
+  uv_fs_req_cleanup(req);
+  scandir_cb_count++;
+}
+
+static void non_existent_scandir_cb(uv_fs_t* req) {
+  uv_dirent_t dent;
+
+  ASSERT_PTR_EQ(req, &scandir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SCANDIR);
+  ASSERT_EQ(req->result, UV_ENOENT);
+  ASSERT_NULL(req->ptr);
+  ASSERT_EQ(UV_ENOENT, uv_fs_scandir_next(req, &dent));
+  uv_fs_req_cleanup(req);
+  scandir_cb_count++;
+}
+
+
+static void file_scandir_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &scandir_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SCANDIR);
+  ASSERT_EQ(req->result, UV_ENOTDIR);
+  ASSERT_NULL(req->ptr);
+  uv_fs_req_cleanup(req);
+  scandir_cb_count++;
+}
+
+
+static void stat_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &stat_req);
+  ASSERT(req->fs_type == UV_FS_STAT || req->fs_type == UV_FS_LSTAT);
+  ASSERT_OK(req->result);
+  ASSERT(req->ptr);
+  stat_cb_count++;
+  uv_fs_req_cleanup(req);
+  ASSERT(!req->ptr);
+}
+
+static void stat_batch_cb(uv_fs_t* req) {
+  ASSERT(req->fs_type == UV_FS_STAT || req->fs_type == UV_FS_LSTAT);
+  ASSERT_OK(req->result);
+  ASSERT(req->ptr);
+  stat_cb_count++;
+  uv_fs_req_cleanup(req);
+  ASSERT(!req->ptr);
+}
+
+
+static void sendfile_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &sendfile_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SENDFILE);
+  ASSERT_EQ(65545, req->result);
+  sendfile_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void sendfile_nodata_cb(uv_fs_t* req) {
+  ASSERT_PTR_EQ(req, &sendfile_req);
+  ASSERT_EQ(req->fs_type, UV_FS_SENDFILE);
+  ASSERT_OK(req->result);
+  sendfile_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+static void open_noent_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  ASSERT_EQ(req->result, UV_ENOENT);
+  open_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void open_nametoolong_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  ASSERT_EQ(req->result, UV_ENAMETOOLONG);
+  open_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+static void open_loop_cb(uv_fs_t* req) {
+  ASSERT_EQ(req->fs_type, UV_FS_OPEN);
+  ASSERT_EQ(req->result, UV_ELOOP);
+  open_cb_count++;
+  uv_fs_req_cleanup(req);
+}
+
+
+TEST_IMPL(fs_file_noent) {
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "does_not_exist", UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_EQ(r, UV_ENOENT);
+  ASSERT_EQ(req.result, UV_ENOENT);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(loop, &req, "does_not_exist", UV_FS_O_RDONLY, 0,
+                 open_noent_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(open_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, open_cb_count);
+
+  /* TODO add EACCES test */
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_file_nametoolong) {
+  uv_fs_t req;
+  int r;
+  char name[TOO_LONG_NAME_LENGTH + 1];
+
+  loop = uv_default_loop();
+
+  memset(name, 'a', TOO_LONG_NAME_LENGTH);
+  name[TOO_LONG_NAME_LENGTH] = 0;
+
+  r = uv_fs_open(NULL, &req, name, UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_EQ(r, UV_ENAMETOOLONG);
+  ASSERT_EQ(req.result, UV_ENAMETOOLONG);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(loop, &req, name, UV_FS_O_RDONLY, 0, open_nametoolong_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(open_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, open_cb_count);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_file_loop) {
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+
+  unlink("test_symlink");
+  r = uv_fs_symlink(NULL, &req, "test_symlink", "test_symlink", 0, NULL);
+#ifdef _WIN32
+  /*
+   * Symlinks are only suported but only when elevated, otherwise
+   * we'll see UV_EPERM.
+   */
+  if (r == UV_EPERM)
+    return 0;
+#elif defined(__MSYS__)
+  /* MSYS2's approximation of symlinks with copies does not work for broken
+     links.  */
+  if (r == UV_ENOENT)
+    return 0;
+#endif
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(NULL, &req, "test_symlink", UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_EQ(r, UV_ELOOP);
+  ASSERT_EQ(req.result, UV_ELOOP);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(loop, &req, "test_symlink", UV_FS_O_RDONLY, 0, open_loop_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(open_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, open_cb_count);
+
+  unlink("test_symlink");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+static void check_utime(const char* path,
+                        double atime,
+                        double mtime,
+                        int test_lutime) {
+  uv_stat_t* s;
+  uv_fs_t req;
+  int r;
+
+  if (test_lutime)
+    r = uv_fs_lstat(loop, &req, path, NULL);
+  else
+    r = uv_fs_stat(loop, &req, path, NULL);
+
+  ASSERT_OK(r);
+
+  ASSERT_OK(req.result);
+  s = &req.statbuf;
+
+  if (isfinite(atime)) {
+    /* Test sub-second timestamps only when supported (such as Windows with
+     * NTFS). Some other platforms support sub-second timestamps, but that
+     * support is filesystem-dependent. Notably OS X (HFS Plus) does NOT
+     * support sub-second timestamps. But kernels may round or truncate in
+     * either direction, so we may accept either possible answer.
+     */
+    if (s->st_atim.tv_nsec == 0) {
+      if (is_win32)
+        ASSERT_DOUBLE_EQ(atime, (long) atime);
+      if (atime > 0 || (long) atime == atime)
+        ASSERT_EQ(s->st_atim.tv_sec, (long) atime);
+      ASSERT_GE(s->st_atim.tv_sec, (long) atime - 1);
+      ASSERT_LE(s->st_atim.tv_sec, (long) atime);
+    } else {
+      double st_atim;
+      /* TODO(vtjnash): would it be better to normalize this? */
+      if (!is_apple_or_sunpro_c)
+        ASSERT_DOUBLE_GE(s->st_atim.tv_nsec, 0);
+      st_atim = s->st_atim.tv_sec + s->st_atim.tv_nsec / 1e9;
+      /* Linux does not allow reading reliably the atime of a symlink
+       * since readlink() can update it
+       */
+      if (!test_lutime)
+        ASSERT_DOUBLE_EQ(st_atim, atime);
+    }
+  } else if (isinf(atime)) {
+    /* We test with timestamps that are in the distant past
+     * (if you're a Gen Z-er) so check it's more recent than that.
+     */
+      ASSERT_GT(s->st_atim.tv_sec, 1739710000);
+  } else {
+    ASSERT_OK(0);
+  }
+
+  if (isfinite(mtime)) {
+    /* Test sub-second timestamps only when supported (such as Windows with
+     * NTFS). Some other platforms support sub-second timestamps, but that
+     * support is filesystem-dependent. Notably OS X (HFS Plus) does NOT
+     * support sub-second timestamps. But kernels may round or truncate in
+     * either direction, so we may accept either possible answer.
+     */
+    if (s->st_mtim.tv_nsec == 0) {
+      if (is_win32)
+        ASSERT_DOUBLE_EQ(mtime, (long) atime);
+      if (mtime > 0 || (long) mtime == mtime)
+        ASSERT_EQ(s->st_mtim.tv_sec, (long) mtime);
+      ASSERT_GE(s->st_mtim.tv_sec, (long) mtime - 1);
+      ASSERT_LE(s->st_mtim.tv_sec, (long) mtime);
+    } else {
+      double st_mtim;
+      /* TODO(vtjnash): would it be better to normalize this? */
+      if (!is_apple_or_sunpro_c)
+        ASSERT_DOUBLE_GE(s->st_mtim.tv_nsec, 0);
+      st_mtim = s->st_mtim.tv_sec + s->st_mtim.tv_nsec / 1e9;
+      ASSERT_DOUBLE_EQ(st_mtim, mtime);
+    }
+  } else if (isinf(mtime)) {
+    /* We test with timestamps that are in the distant past
+     * (if you're a Gen Z-er) so check it's more recent than that.
+     */
+      ASSERT_GT(s->st_mtim.tv_sec, 1739710000);
+  } else {
+    ASSERT_OK(0);
+  }
+
+  uv_fs_req_cleanup(&req);
+}
+
+
+static void utime_cb(uv_fs_t* req) {
+  utime_check_t* c;
+
+  ASSERT_PTR_EQ(req, &utime_req);
+  ASSERT_OK(req->result);
+  ASSERT_EQ(req->fs_type, UV_FS_UTIME);
+
+  c = req->data;
+  check_utime(c->path, c->atime, c->mtime, /* test_lutime */ 0);
+
+  uv_fs_req_cleanup(req);
+  utime_cb_count++;
+}
+
+
+static void futime_cb(uv_fs_t* req) {
+  utime_check_t* c;
+
+  ASSERT_PTR_EQ(req, &futime_req);
+  ASSERT_OK(req->result);
+  ASSERT_EQ(req->fs_type, UV_FS_FUTIME);
+
+  c = req->data;
+  check_utime(c->path, c->atime, c->mtime, /* test_lutime */ 0);
+
+  uv_fs_req_cleanup(req);
+  futime_cb_count++;
+}
+
+
+static void lutime_cb(uv_fs_t* req) {
+  utime_check_t* c;
+
+  ASSERT_OK(req->result);
+  ASSERT_EQ(req->fs_type, UV_FS_LUTIME);
+
+  c = req->data;
+  check_utime(c->path, c->atime, c->mtime, /* test_lutime */ 1);
+
+  uv_fs_req_cleanup(req);
+  lutime_cb_count++;
+}
+
+
+TEST_IMPL(fs_file_async) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(loop, &open_req1, "test_file", UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IRUSR | S_IWUSR, create_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, create_cb_count);
+  ASSERT_EQ(1, write_cb_count);
+  ASSERT_EQ(1, fsync_cb_count);
+  ASSERT_EQ(1, fdatasync_cb_count);
+  ASSERT_EQ(1, close_cb_count);
+
+  r = uv_fs_rename(loop, &rename_req, "test_file", "test_file2", rename_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, create_cb_count);
+  ASSERT_EQ(1, write_cb_count);
+  ASSERT_EQ(1, close_cb_count);
+  ASSERT_EQ(1, rename_cb_count);
+
+  r = uv_fs_open(loop, &open_req1, "test_file2", UV_FS_O_RDWR, 0, open_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, open_cb_count);
+  ASSERT_EQ(1, read_cb_count);
+  ASSERT_EQ(2, close_cb_count);
+  ASSERT_EQ(1, rename_cb_count);
+  ASSERT_EQ(1, create_cb_count);
+  ASSERT_EQ(1, write_cb_count);
+  ASSERT_EQ(1, ftruncate_cb_count);
+
+  r = uv_fs_open(loop, &open_req1, "test_file2", UV_FS_O_RDONLY, 0, open_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(2, open_cb_count);
+  ASSERT_EQ(2, read_cb_count);
+  ASSERT_EQ(3, close_cb_count);
+  ASSERT_EQ(1, rename_cb_count);
+  ASSERT_EQ(1, unlink_cb_count);
+  ASSERT_EQ(1, create_cb_count);
+  ASSERT_EQ(1, write_cb_count);
+  ASSERT_EQ(1, ftruncate_cb_count);
+
+  /* Cleanup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static void fs_file_sync(int add_flags) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(loop, &open_req1, "test_file",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT | add_flags, S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDWR | add_flags, 0,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(read_req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_ftruncate(NULL, &ftruncate_req, open_req1.result, 7, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(ftruncate_req.result);
+  uv_fs_req_cleanup(&ftruncate_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_rename(NULL, &rename_req, "test_file", "test_file2", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(rename_req.result);
+  uv_fs_req_cleanup(&rename_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file2", UV_FS_O_RDONLY | add_flags, 0,
+      NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(read_req.result, 0);
+  ASSERT_OK(strcmp(buf, "test-bu"));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_unlink(NULL, &unlink_req, "test_file2", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(unlink_req.result);
+  uv_fs_req_cleanup(&unlink_req);
+
+  /* Cleanup */
+  unlink("test_file");
+  unlink("test_file2");
+}
+TEST_IMPL(fs_file_sync) {
+  fs_file_sync(0);
+  fs_file_sync(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+TEST_IMPL(fs_posix_delete) {
+  int r;
+
+  /* Setup. */
+  unlink("test_dir/file");
+  rmdir("test_dir");
+
+  r = uv_fs_mkdir(NULL, &mkdir_req, "test_dir", 0755, NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_open(NULL, &open_req_noclose, "test_dir/file", UV_FS_O_WRONLY | UV_FS_O_CREAT, S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req_noclose);
+
+  /* should not be possible to delete the non-empty dir */
+  r = uv_fs_rmdir(NULL, &rmdir_req, "test_dir", NULL);
+  ASSERT((r == UV_ENOTEMPTY) || (r == UV_EEXIST));
+  ASSERT_EQ(r, rmdir_req.result);
+  uv_fs_req_cleanup(&rmdir_req);
+
+  r = uv_fs_rmdir(NULL, &rmdir_req, "test_dir/file", NULL);
+  ASSERT((r == UV_ENOTDIR) || (r == UV_ENOENT));
+  ASSERT_EQ(r, rmdir_req.result);
+  uv_fs_req_cleanup(&rmdir_req);
+
+  r = uv_fs_unlink(NULL, &unlink_req, "test_dir/file", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(unlink_req.result);
+  uv_fs_req_cleanup(&unlink_req);
+
+  /* delete the dir while the file is still open, which should succeed on posix */
+  r = uv_fs_rmdir(NULL, &rmdir_req, "test_dir", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(rmdir_req.result);
+  uv_fs_req_cleanup(&rmdir_req);
+
+  /* Cleanup */
+  r = uv_fs_close(NULL, &close_req, open_req_noclose.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+static void fs_file_write_null_buffer(int add_flags) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &open_req1, "test_file",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT | add_flags, S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(NULL, 0);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(write_req.result);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  unlink("test_file");
+}
+TEST_IMPL(fs_file_write_null_buffer) {
+  fs_file_write_null_buffer(0);
+  fs_file_write_null_buffer(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_async_dir) {
+  int r;
+  uv_dirent_t dent;
+
+  /* Setup */
+  unlink("test_dir/file1");
+  unlink("test_dir/file2");
+  rmdir("test_dir");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_mkdir(loop, &mkdir_req, "test_dir", 0755, mkdir_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, mkdir_cb_count);
+
+  /* Create 2 files synchronously. */
+  r = uv_fs_open(NULL, &open_req1, "test_dir/file1",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_dir/file2",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_scandir(loop, &scandir_req, "test_dir", 0, scandir_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, scandir_cb_count);
+
+  /* sync uv_fs_scandir */
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir", 0, NULL);
+  ASSERT_EQ(2, r);
+  ASSERT_EQ(2, scandir_req.result);
+  ASSERT(scandir_req.ptr);
+  while (UV_EOF != uv_fs_scandir_next(&scandir_req, &dent)) {
+    ASSERT(strcmp(dent.name, "file1") == 0 || strcmp(dent.name, "file2") == 0);
+    assert_is_file_type(dent);
+  }
+  uv_fs_req_cleanup(&scandir_req);
+  ASSERT(!scandir_req.ptr);
+
+  r = uv_fs_stat(loop, &stat_req, "test_dir", stat_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  r = uv_fs_stat(loop, &stat_req, "test_dir/", stat_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  r = uv_fs_lstat(loop, &stat_req, "test_dir", stat_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  r = uv_fs_lstat(loop, &stat_req, "test_dir/", stat_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(4, stat_cb_count);
+
+  r = uv_fs_unlink(loop, &unlink_req, "test_dir/file1", unlink_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, unlink_cb_count);
+
+  r = uv_fs_unlink(loop, &unlink_req, "test_dir/file2", unlink_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(2, unlink_cb_count);
+
+  r = uv_fs_rmdir(loop, &rmdir_req, "test_dir", rmdir_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, rmdir_cb_count);
+
+  /* Cleanup */
+  unlink("test_dir/file1");
+  unlink("test_dir/file2");
+  rmdir("test_dir");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static int test_sendfile(void (*setup)(int), uv_fs_cb cb, size_t expected_size) {
+  int f, r;
+  struct stat s1, s2;
+  uv_fs_t req;
+  char buf1[1];
+
+  loop = uv_default_loop();
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  f = open("test_file", UV_FS_O_WRONLY | UV_FS_O_CREAT, S_IWUSR | S_IRUSR);
+  ASSERT_NE(f, -1);
+
+  if (setup != NULL)
+    setup(f);
+
+  r = close(f);
+  ASSERT_OK(r);
+
+  /* Test starts here. */
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  r = uv_fs_open(NULL, &open_req2, "test_file2", UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req2.result, 0);
+  uv_fs_req_cleanup(&open_req2);
+
+  r = uv_fs_sendfile(loop, &sendfile_req, open_req2.result, open_req1.result,
+      1, 131072, cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  ASSERT_EQ(1, sendfile_cb_count);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+  r = uv_fs_close(NULL, &close_req, open_req2.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  memset(&s1, 0, sizeof(s1));
+  memset(&s2, 0, sizeof(s2));
+  ASSERT_OK(stat("test_file", &s1));
+  ASSERT_OK(stat("test_file2", &s2));
+  ASSERT_EQ(s2.st_size, expected_size);
+
+  if (expected_size > 0) {
+    ASSERT_UINT64_EQ(s1.st_size, s2.st_size + 1);
+    r = uv_fs_open(NULL, &open_req1, "test_file2", UV_FS_O_RDWR, 0, NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(open_req1.result, 0);
+    uv_fs_req_cleanup(&open_req1);
+
+    memset(buf1, 0, sizeof(buf1));
+    iov = uv_buf_init(buf1, sizeof(buf1));
+    r = uv_fs_read(NULL, &req, open_req1.result, &iov, 1, -1, NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(req.result, 0);
+    ASSERT_EQ(buf1[0], 'e'); /* 'e' from begin */
+    uv_fs_req_cleanup(&req);
+  } else {
+    ASSERT_UINT64_EQ(s1.st_size, s2.st_size);
+  }
+
+  /* Cleanup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static void sendfile_setup(int f) {
+  ASSERT_EQ(6, write(f, "begin\n", 6));
+  ASSERT_EQ(65542, lseek(f, 65536, SEEK_CUR));
+  ASSERT_EQ(4, write(f, "end\n", 4));
+}
+
+
+TEST_IMPL(fs_async_sendfile) {
+  return test_sendfile(sendfile_setup, sendfile_cb, 65545);
+}
+
+
+TEST_IMPL(fs_async_sendfile_nodata) {
+  return test_sendfile(NULL, sendfile_nodata_cb, 0);
+}
+
+
+TEST_IMPL(fs_mkdtemp) {
+  int r;
+  const char* path_template = "test_dir_XXXXXX";
+
+  loop = uv_default_loop();
+
+  r = uv_fs_mkdtemp(loop, &mkdtemp_req1, path_template, mkdtemp_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, mkdtemp_cb_count);
+
+  /* sync mkdtemp */
+  r = uv_fs_mkdtemp(NULL, &mkdtemp_req2, path_template, NULL);
+  ASSERT_OK(r);
+  check_mkdtemp_result(&mkdtemp_req2);
+
+  /* mkdtemp return different values on subsequent calls */
+  ASSERT_NE(0, strcmp(mkdtemp_req1.path, mkdtemp_req2.path));
+
+  /* Cleanup */
+  rmdir(mkdtemp_req1.path);
+  rmdir(mkdtemp_req2.path);
+  uv_fs_req_cleanup(&mkdtemp_req1);
+  uv_fs_req_cleanup(&mkdtemp_req2);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_mkstemp) {
+  int r;
+  int fd;
+  const char path_template[] = "test_file_XXXXXX";
+  uv_fs_t req;
+
+  loop = uv_default_loop();
+
+  r = uv_fs_mkstemp(loop, &mkstemp_req1, path_template, mkstemp_cb);
+  ASSERT_OK(r);
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, mkstemp_cb_count);
+
+  /* sync mkstemp */
+  r = uv_fs_mkstemp(NULL, &mkstemp_req2, path_template, NULL);
+  ASSERT_GE(r, 0);
+  check_mkstemp_result(&mkstemp_req2);
+
+  /* mkstemp return different values on subsequent calls */
+  ASSERT_NE(0, strcmp(mkstemp_req1.path, mkstemp_req2.path));
+
+  /* invalid template returns EINVAL */
+  ASSERT_EQ(UV_EINVAL, uv_fs_mkstemp(NULL, &mkstemp_req3, "test_file", NULL));
+
+  /* Make sure that path is empty string */
+  ASSERT_OK(strlen(mkstemp_req3.path));
+
+  uv_fs_req_cleanup(&mkstemp_req3);
+
+  /* We can write to the opened file */
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, mkstemp_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  /* Cleanup */
+  uv_fs_close(NULL, &req, mkstemp_req1.result, NULL);
+  uv_fs_req_cleanup(&req);
+  uv_fs_close(NULL, &req, mkstemp_req2.result, NULL);
+  uv_fs_req_cleanup(&req);
+
+  fd = uv_fs_open(NULL, &req, mkstemp_req1.path, UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_GE(fd, 0);
+  uv_fs_req_cleanup(&req);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &req, fd, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+  uv_fs_req_cleanup(&req);
+
+  uv_fs_close(NULL, &req, fd, NULL);
+  uv_fs_req_cleanup(&req);
+
+  unlink(mkstemp_req1.path);
+  unlink(mkstemp_req2.path);
+  uv_fs_req_cleanup(&mkstemp_req1);
+  uv_fs_req_cleanup(&mkstemp_req2);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_fstat) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+  uv_stat_t* s;
+#ifndef _WIN32
+  struct stat t;
+#endif
+
+#if defined(__s390__) && defined(__QEMU__)
+  /* qemu-user-s390x has this weird bug where statx() reports nanoseconds
+   * but plain fstat() does not.
+   */
+  RETURN_SKIP("Test does not currently work in QEMU");
+#endif
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+#ifndef _WIN32
+  memset(&t, 0, sizeof(t));
+  ASSERT_OK(fstat(file, &t));
+  ASSERT_OK(uv_fs_fstat(NULL, &req, file, NULL));
+  ASSERT_OK(req.result);
+  s = req.ptr;
+# if defined(__APPLE__)
+  ASSERT_EQ(s->st_birthtim.tv_sec, t.st_birthtimespec.tv_sec);
+  ASSERT_EQ(s->st_birthtim.tv_nsec, t.st_birthtimespec.tv_nsec);
+# elif defined(__linux__)
+  /* If statx() is supported, the birth time should be equal to the change time
+   * because we just created the file. On older kernels, it's set to zero.
+   */
+  ASSERT(s->st_birthtim.tv_sec == 0 ||
+         s->st_birthtim.tv_sec == t.st_ctim.tv_sec);
+  ASSERT(s->st_birthtim.tv_nsec == 0 ||
+         s->st_birthtim.tv_nsec == t.st_ctim.tv_nsec);
+# endif
+#endif
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  memset(&req.statbuf, 0xaa, sizeof(req.statbuf));
+  r = uv_fs_fstat(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  s = req.ptr;
+  ASSERT_EQ(s->st_size, sizeof(test_buf));
+
+#ifndef _WIN32
+  r = fstat(file, &t);
+  ASSERT_OK(r);
+
+  ASSERT_EQ(s->st_dev, (uint64_t) t.st_dev);
+  ASSERT_EQ(s->st_mode, (uint64_t) t.st_mode);
+  ASSERT_EQ(s->st_nlink, (uint64_t) t.st_nlink);
+  ASSERT_EQ(s->st_uid, (uint64_t) t.st_uid);
+  ASSERT_EQ(s->st_gid, (uint64_t) t.st_gid);
+  ASSERT_EQ(s->st_rdev, (uint64_t) t.st_rdev);
+  ASSERT_EQ(s->st_ino, (uint64_t) t.st_ino);
+  ASSERT_EQ(s->st_size, (uint64_t) t.st_size);
+  ASSERT_EQ(s->st_blksize, (uint64_t) t.st_blksize);
+  ASSERT_EQ(s->st_blocks, (uint64_t) t.st_blocks);
+#if defined(__APPLE__)
+  ASSERT_EQ(s->st_atim.tv_sec, t.st_atimespec.tv_sec);
+  ASSERT_EQ(s->st_atim.tv_nsec, t.st_atimespec.tv_nsec);
+  ASSERT_EQ(s->st_mtim.tv_sec, t.st_mtimespec.tv_sec);
+  ASSERT_EQ(s->st_mtim.tv_nsec, t.st_mtimespec.tv_nsec);
+  ASSERT_EQ(s->st_ctim.tv_sec, t.st_ctimespec.tv_sec);
+  ASSERT_EQ(s->st_ctim.tv_nsec, t.st_ctimespec.tv_nsec);
+#elif defined(_AIX)    || \
+      defined(__MVS__)
+  ASSERT_EQ(s->st_atim.tv_sec, t.st_atime);
+  ASSERT_OK(s->st_atim.tv_nsec);
+  ASSERT_EQ(s->st_mtim.tv_sec, t.st_mtime);
+  ASSERT_OK(s->st_mtim.tv_nsec);
+  ASSERT_EQ(s->st_ctim.tv_sec, t.st_ctime);
+  ASSERT_OK(s->st_ctim.tv_nsec);
+#elif defined(__ANDROID__)
+  ASSERT_EQ(s->st_atim.tv_sec, t.st_atime);
+  ASSERT_EQ(s->st_atim.tv_nsec, t.st_atimensec);
+  ASSERT_EQ(s->st_mtim.tv_sec, t.st_mtime);
+  ASSERT_EQ(s->st_mtim.tv_nsec, t.st_mtimensec);
+  ASSERT_EQ(s->st_ctim.tv_sec, t.st_ctime);
+  ASSERT_EQ(s->st_ctim.tv_nsec, t.st_ctimensec);
+#elif defined(__sun)           || \
+      defined(__DragonFly__)   || \
+      defined(__FreeBSD__)     || \
+      defined(__OpenBSD__)     || \
+      defined(__NetBSD__)      || \
+      defined(_GNU_SOURCE)     || \
+      defined(_BSD_SOURCE)     || \
+      defined(_SVID_SOURCE)    || \
+      defined(_XOPEN_SOURCE)   || \
+      defined(_DEFAULT_SOURCE)
+  ASSERT_EQ(s->st_atim.tv_sec, t.st_atim.tv_sec);
+  ASSERT_EQ(s->st_atim.tv_nsec, t.st_atim.tv_nsec);
+  ASSERT_EQ(s->st_mtim.tv_sec, t.st_mtim.tv_sec);
+  ASSERT_EQ(s->st_mtim.tv_nsec, t.st_mtim.tv_nsec);
+  ASSERT_EQ(s->st_ctim.tv_sec, t.st_ctim.tv_sec);
+  ASSERT_EQ(s->st_ctim.tv_nsec, t.st_ctim.tv_nsec);
+# if defined(__FreeBSD__)    || \
+     defined(__NetBSD__)
+  ASSERT_EQ(s->st_birthtim.tv_sec, t.st_birthtim.tv_sec);
+  ASSERT_EQ(s->st_birthtim.tv_nsec, t.st_birthtim.tv_nsec);
+# endif
+#else
+  ASSERT_EQ(s->st_atim.tv_sec, t.st_atime);
+  ASSERT_OK(s->st_atim.tv_nsec);
+  ASSERT_EQ(s->st_mtim.tv_sec, t.st_mtime);
+  ASSERT_OK(s->st_mtim.tv_nsec);
+  ASSERT_EQ(s->st_ctim.tv_sec, t.st_ctime);
+  ASSERT_OK(s->st_ctim.tv_nsec);
+#endif
+#endif
+
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__NetBSD__)
+  ASSERT_EQ(s->st_flags, t.st_flags);
+  ASSERT_EQ(s->st_gen, t.st_gen);
+#else
+  ASSERT_OK(s->st_flags);
+  ASSERT_OK(s->st_gen);
+#endif
+
+  uv_fs_req_cleanup(&req);
+
+  /* Now do the uv_fs_fstat call asynchronously */
+  r = uv_fs_fstat(loop, &req, file, fstat_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, fstat_cb_count);
+
+
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_fstat_st_dev) {
+  uv_fs_t req;
+  uv_fs_t req_link;
+  uv_loop_t* loop = uv_default_loop();
+  char* test_file = "tmp_st_dev";
+  char* symlink_file = "tmp_st_dev_link";
+
+  unlink(test_file);
+  unlink(symlink_file);
+
+  // Create file
+  int r = uv_fs_open(NULL, &req, test_file, UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  uv_fs_req_cleanup(&req);
+
+  // Create a symlink
+  r = uv_fs_symlink(loop, &req, test_file, symlink_file, 0, NULL);
+  ASSERT_EQ(r, 0);
+  uv_fs_req_cleanup(&req);
+
+  // Call uv_fs_fstat for file
+  r = uv_fs_stat(loop, &req, test_file, NULL);
+  ASSERT_EQ(r, 0);
+
+  // Call uv_fs_fstat for symlink
+  r = uv_fs_stat(loop, &req_link, symlink_file, NULL);
+  ASSERT_EQ(r, 0);
+
+  // Compare st_dev
+  ASSERT_EQ(((uv_stat_t*)req.ptr)->st_dev, ((uv_stat_t*)req_link.ptr)->st_dev);
+
+  // Cleanup
+  uv_fs_req_cleanup(&req);
+  uv_fs_req_cleanup(&req_link);
+  unlink(test_file);
+  unlink(symlink_file);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_fstat_stdio) {
+  int fd;
+  int res;
+  uv_fs_t req;
+#ifdef _WIN32
+  uv_stat_t* st;
+  DWORD ft;
+#endif
+
+  for (fd = 0; fd <= 2; ++fd) {
+    res = uv_fs_fstat(NULL, &req, fd, NULL);
+    ASSERT_OK(res);
+    ASSERT_OK(req.result);
+
+#ifdef _WIN32
+    st = req.ptr;
+    ft = uv_guess_handle(fd);
+    switch (ft) {
+    case UV_TTY:
+    case UV_NAMED_PIPE:
+      ASSERT_EQ(st->st_mode, (ft == UV_TTY ? S_IFCHR : S_IFIFO));
+      ASSERT_EQ(1, st->st_nlink);
+      ASSERT_EQ(st->st_rdev,
+                (ft == UV_TTY ? FILE_DEVICE_CONSOLE : FILE_DEVICE_NAMED_PIPE)
+                << 16);
+      break;
+    default:
+      break;
+    }
+#endif
+
+    uv_fs_req_cleanup(&req);
+  }
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+TEST_IMPL(fs_access) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+
+  /* Setup. */
+  unlink("test_file");
+  rmdir("test_dir");
+
+  loop = uv_default_loop();
+
+  /* File should not exist */
+  r = uv_fs_access(NULL, &req, "test_file", F_OK, NULL);
+  ASSERT_LT(r, 0);
+  ASSERT_LT(req.result, 0);
+  uv_fs_req_cleanup(&req);
+
+  /* File should not exist */
+  r = uv_fs_access(loop, &req, "test_file", F_OK, access_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, access_cb_count);
+  access_cb_count = 0; /* reset for the next test */
+
+  /* Create file */
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  /* File should exist */
+  r = uv_fs_access(NULL, &req, "test_file", F_OK, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* File should exist */
+  r = uv_fs_access(loop, &req, "test_file", F_OK, access_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, access_cb_count);
+  access_cb_count = 0; /* reset for the next test */
+
+  /* Close file */
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* Directory access */
+  r = uv_fs_mkdir(NULL, &req, "test_dir", 0777, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_access(NULL, &req, "test_dir", W_OK, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+  rmdir("test_dir");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_chmod) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+#ifndef _WIN32
+  /* Make the file write-only */
+  r = uv_fs_chmod(NULL, &req, "test_file", 0200, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  check_permission("test_file", 0200);
+#endif
+
+  /* Make the file read-only */
+  r = uv_fs_chmod(NULL, &req, "test_file", 0400, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  check_permission("test_file", 0400);
+
+  /* Make the file read+write with sync uv_fs_fchmod */
+  r = uv_fs_fchmod(NULL, &req, file, 0600, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  check_permission("test_file", 0600);
+
+#ifndef _WIN32
+  /* async chmod */
+  {
+    static int mode = 0200;
+    req.data = &mode;
+  }
+  r = uv_fs_chmod(loop, &req, "test_file", 0200, chmod_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, chmod_cb_count);
+  chmod_cb_count = 0; /* reset for the next test */
+#endif
+
+  /* async chmod */
+  {
+    static int mode = 0400;
+    req.data = &mode;
+  }
+  r = uv_fs_chmod(loop, &req, "test_file", 0400, chmod_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, chmod_cb_count);
+
+  /* async fchmod */
+  {
+    static int mode = 0600;
+    req.data = &mode;
+  }
+  r = uv_fs_fchmod(loop, &req, file, 0600, fchmod_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, fchmod_cb_count);
+
+  uv_fs_close(loop, &req, file, NULL);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_unlink_readonly) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL,
+                 &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  uv_fs_close(loop, &req, file, NULL);
+
+  /* Make the file read-only */
+  r = uv_fs_chmod(NULL, &req, "test_file", 0400, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  check_permission("test_file", 0400);
+
+  /* Try to unlink the file */
+  r = uv_fs_unlink(NULL, &req, "test_file", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /*
+  * Run the loop just to check we don't have make any extraneous uv_ref()
+  * calls. This should drop out immediately.
+  */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  uv_fs_chmod(NULL, &req, "test_file", 0600, NULL);
+  uv_fs_req_cleanup(&req);
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+#ifdef _WIN32
+TEST_IMPL(fs_unlink_archive_readonly) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL,
+                 &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  uv_fs_close(loop, &req, file, NULL);
+
+  /* Make the file read-only and clear archive flag */
+  r = SetFileAttributes("test_file", FILE_ATTRIBUTE_READONLY);
+  ASSERT(r);
+  uv_fs_req_cleanup(&req);
+
+  check_permission("test_file", 0400);
+
+  /* Try to unlink the file */
+  r = uv_fs_unlink(NULL, &req, "test_file", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /*
+  * Run the loop just to check we don't have make any extraneous uv_ref()
+  * calls. This should drop out immediately.
+  */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  uv_fs_chmod(NULL, &req, "test_file", 0600, NULL);
+  uv_fs_req_cleanup(&req);
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+#endif
+
+TEST_IMPL(fs_chown) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file_link");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  /* sync chown */
+  r = uv_fs_chown(NULL, &req, "test_file", -1, -1, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* sync fchown */
+  r = uv_fs_fchown(NULL, &req, file, -1, -1, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* async chown */
+  r = uv_fs_chown(loop, &req, "test_file", -1, -1, chown_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, chown_cb_count);
+
+#ifndef __MVS__
+  /* chown to root (fail) */
+  chown_cb_count = 0;
+  r = uv_fs_chown(loop, &req, "test_file", 0, 0, chown_root_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, chown_cb_count);
+#endif
+
+  /* async fchown */
+  r = uv_fs_fchown(loop, &req, file, -1, -1, fchown_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, fchown_cb_count);
+
+#ifndef __HAIKU__
+  /* Haiku doesn't support hardlink */
+  /* sync link */
+  r = uv_fs_link(NULL, &req, "test_file", "test_file_link", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* sync lchown */
+  r = uv_fs_lchown(NULL, &req, "test_file_link", -1, -1, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* async lchown */
+  r = uv_fs_lchown(loop, &req, "test_file_link", -1, -1, lchown_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, lchown_cb_count);
+#endif
+
+  /* Close file */
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+  unlink("test_file_link");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_link) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+  uv_file link;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file_link");
+  unlink("test_file_link2");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  uv_fs_close(loop, &req, file, NULL);
+
+  /* sync link */
+  r = uv_fs_link(NULL, &req, "test_file", "test_file_link", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(NULL, &req, "test_file_link", UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  link = req.result;
+  uv_fs_req_cleanup(&req);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &req, link, &iov, 1, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+
+  close(link);
+
+  /* async link */
+  r = uv_fs_link(loop, &req, "test_file", "test_file_link2", link_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, link_cb_count);
+
+  r = uv_fs_open(NULL, &req, "test_file_link2", UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  link = req.result;
+  uv_fs_req_cleanup(&req);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &req, link, &iov, 1, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+
+  uv_fs_close(loop, &req, link, NULL);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+  unlink("test_file_link");
+  unlink("test_file_link2");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_readlink) {
+  /* Must return UV_ENOENT on an inexistent file */
+  {
+    uv_fs_t req;
+
+    loop = uv_default_loop();
+    ASSERT_OK(uv_fs_readlink(loop, &req, "no_such_file", dummy_cb));
+    ASSERT_OK(uv_run(loop, UV_RUN_DEFAULT));
+    ASSERT_EQ(1, dummy_cb_count);
+    ASSERT_NULL(req.ptr);
+    ASSERT_EQ(req.result, UV_ENOENT);
+    uv_fs_req_cleanup(&req);
+
+    ASSERT_EQ(UV_ENOENT, uv_fs_readlink(NULL, &req, "no_such_file", NULL));
+    ASSERT_NULL(req.ptr);
+    ASSERT_EQ(req.result, UV_ENOENT);
+    uv_fs_req_cleanup(&req);
+  }
+
+  /* Must return UV_EINVAL on a non-symlink file */
+  {
+    int r;
+    uv_fs_t req;
+    uv_file file;
+
+    /* Setup */
+
+    /* Create a non-symlink file */
+    r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                   S_IWUSR | S_IRUSR, NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(req.result, 0);
+    file = req.result;
+    uv_fs_req_cleanup(&req);
+
+    r = uv_fs_close(NULL, &req, file, NULL);
+    ASSERT_OK(r);
+    ASSERT_OK(req.result);
+    uv_fs_req_cleanup(&req);
+
+    /* Test */
+    r = uv_fs_readlink(NULL, &req, "test_file", NULL);
+    ASSERT_EQ(r, UV_EINVAL);
+    uv_fs_req_cleanup(&req);
+
+    /* Cleanup */
+    unlink("test_file");
+  }
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_realpath) {
+  uv_fs_t req;
+
+  loop = uv_default_loop();
+  ASSERT_OK(uv_fs_realpath(loop, &req, "no_such_file", dummy_cb));
+  ASSERT_OK(uv_run(loop, UV_RUN_DEFAULT));
+  ASSERT_EQ(1, dummy_cb_count);
+  ASSERT_NULL(req.ptr);
+  ASSERT_EQ(req.result, UV_ENOENT);
+  uv_fs_req_cleanup(&req);
+
+  ASSERT_EQ(UV_ENOENT, uv_fs_realpath(NULL, &req, "no_such_file", NULL));
+  ASSERT_NULL(req.ptr);
+  ASSERT_EQ(req.result, UV_ENOENT);
+  uv_fs_req_cleanup(&req);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_symlink) {
+  int r;
+  uv_fs_t req;
+  uv_file file;
+  uv_file link;
+  char test_file_abs_buf[PATHMAX];
+  size_t test_file_abs_size;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file_symlink");
+  unlink("test_file_symlink2");
+  unlink("test_file_symlink_symlink");
+  unlink("test_file_symlink2_symlink");
+  test_file_abs_size = sizeof(test_file_abs_buf);
+#ifdef _WIN32
+  uv_cwd(test_file_abs_buf, &test_file_abs_size);
+  strcat(test_file_abs_buf, "\\test_file");
+#else
+  uv_cwd(test_file_abs_buf, &test_file_abs_size);
+  strcat(test_file_abs_buf, "/test_file");
+#endif
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result;
+  uv_fs_req_cleanup(&req);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &req, file, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_EQ(req.result, sizeof(test_buf));
+  uv_fs_req_cleanup(&req);
+
+  uv_fs_close(loop, &req, file, NULL);
+
+  /* sync symlink */
+  r = uv_fs_symlink(NULL, &req, "test_file", "test_file_symlink", 0, NULL);
+#ifdef _WIN32
+  if (r < 0) {
+    if (r == UV_ENOTSUP) {
+      /*
+       * Windows doesn't support symlinks on older versions.
+       * We just pass the test and bail out early if we get ENOTSUP.
+       */
+      return 0;
+    } else if (r == UV_EPERM) {
+      /*
+       * Creating a symlink is only allowed when running elevated.
+       * We pass the test and bail out early if we get UV_EPERM.
+       */
+      return 0;
+    }
+  }
+#endif
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(NULL, &req, "test_file_symlink", UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  link = req.result;
+  uv_fs_req_cleanup(&req);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &req, link, &iov, 1, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+
+  uv_fs_close(loop, &req, link, NULL);
+
+  r = uv_fs_symlink(NULL,
+                    &req,
+                    "test_file_symlink",
+                    "test_file_symlink_symlink",
+                    0,
+                    NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+#if defined(__MSYS__)
+  RETURN_SKIP("symlink reading is not supported on MSYS2");
+#endif
+
+  r = uv_fs_readlink(NULL, &req, "test_file_symlink_symlink", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(strcmp(req.ptr, "test_file_symlink"));
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_realpath(NULL, &req, "test_file_symlink_symlink", NULL);
+  ASSERT_OK(r);
+#ifdef _WIN32
+  ASSERT_OK(_stricmp(req.ptr, test_file_abs_buf));
+#else
+  ASSERT_OK(strcmp(req.ptr, test_file_abs_buf));
+#endif
+  uv_fs_req_cleanup(&req);
+
+  /* async link */
+  r = uv_fs_symlink(loop,
+                    &req,
+                    "test_file",
+                    "test_file_symlink2",
+                    0,
+                    symlink_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, symlink_cb_count);
+
+  r = uv_fs_open(NULL, &req, "test_file_symlink2", UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  link = req.result;
+  uv_fs_req_cleanup(&req);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &req, link, &iov, 1, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+
+  uv_fs_close(loop, &req, link, NULL);
+
+  r = uv_fs_symlink(NULL,
+                    &req,
+                    "test_file_symlink2",
+                    "test_file_symlink2_symlink",
+                    0,
+                    NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_readlink(loop, &req, "test_file_symlink2_symlink", readlink_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, readlink_cb_count);
+
+  r = uv_fs_realpath(loop, &req, "test_file", realpath_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, realpath_cb_count);
+
+  /*
+   * Run the loop just to check we don't have make any extraneous uv_ref()
+   * calls. This should drop out immediately.
+   */
+  uv_run(loop, UV_RUN_DEFAULT);
+
+  /* Cleanup. */
+  unlink("test_file");
+  unlink("test_file_symlink");
+  unlink("test_file_symlink_symlink");
+  unlink("test_file_symlink2");
+  unlink("test_file_symlink2_symlink");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+int test_symlink_dir_impl(int type) {
+  uv_fs_t req;
+  int r;
+  char* test_dir;
+  uv_dirent_t dent;
+  static char test_dir_abs_buf[PATHMAX];
+  size_t test_dir_abs_size;
+
+  /* set-up */
+  unlink("test_dir/file1");
+  unlink("test_dir/file2");
+  rmdir("test_dir");
+  rmdir("test_dir_symlink");
+  test_dir_abs_size = sizeof(test_dir_abs_buf);
+
+  loop = uv_default_loop();
+
+  uv_fs_mkdir(NULL, &req, "test_dir", 0777, NULL);
+  uv_fs_req_cleanup(&req);
+
+#ifdef _WIN32
+  strcpy(test_dir_abs_buf, "\\\\?\\");
+  uv_cwd(test_dir_abs_buf + 4, &test_dir_abs_size);
+  test_dir_abs_size += 4;
+  strcat(test_dir_abs_buf, "\\test_dir");
+  test_dir_abs_size += strlen("\\test_dir");
+  test_dir = test_dir_abs_buf;
+#else
+  uv_cwd(test_dir_abs_buf, &test_dir_abs_size);
+  strcat(test_dir_abs_buf, "/test_dir");
+  test_dir_abs_size += strlen("/test_dir");
+  test_dir = "test_dir";
+#endif
+
+  r = uv_fs_symlink(NULL, &req, test_dir, "test_dir_symlink", type, NULL);
+  if (type == UV_FS_SYMLINK_DIR && (r == UV_ENOTSUP || r == UV_EPERM)) {
+    uv_fs_req_cleanup(&req);
+    RETURN_SKIP("this version of Windows doesn't support unprivileged "
+                "creation of directory symlinks");
+  }
+  fprintf(stderr, "r == %i\n", r);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_stat(NULL, &req, "test_dir_symlink", NULL);
+  ASSERT_OK(r);
+  ASSERT(((uv_stat_t*)req.ptr)->st_mode & S_IFDIR);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_lstat(NULL, &req, "test_dir_symlink", NULL);
+  ASSERT_OK(r);
+#if defined(__MSYS__)
+  RETURN_SKIP("symlink reading is not supported on MSYS2");
+#endif
+  ASSERT(((uv_stat_t*)req.ptr)->st_mode & S_IFLNK);
+#ifdef _WIN32
+  ASSERT_EQ(((uv_stat_t*)req.ptr)->st_size, strlen(test_dir + 4));
+#else
+# ifdef __PASE__
+  /* On IBMi PASE, st_size returns the length of the symlink itself. */
+  ASSERT_EQ(((uv_stat_t*)req.ptr)->st_size, strlen("test_dir_symlink"));
+# else
+  ASSERT_EQ(((uv_stat_t*)req.ptr)->st_size, strlen(test_dir));
+# endif
+#endif
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_readlink(NULL, &req, "test_dir_symlink", NULL);
+  ASSERT_OK(r);
+#ifdef _WIN32
+  ASSERT_OK(strcmp(req.ptr, test_dir + 4));
+#else
+  ASSERT_OK(strcmp(req.ptr, test_dir));
+#endif
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_realpath(NULL, &req, "test_dir_symlink", NULL);
+  ASSERT_OK(r);
+#ifdef _WIN32
+  ASSERT_EQ(strlen(req.ptr), test_dir_abs_size - 4);
+  ASSERT_OK(_strnicmp(req.ptr, test_dir + 4, test_dir_abs_size - 4));
+#else
+  ASSERT_OK(strcmp(req.ptr, test_dir_abs_buf));
+#endif
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_dir/file1",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_dir/file2",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir_symlink", 0, NULL);
+  ASSERT_EQ(2, r);
+  ASSERT_EQ(2, scandir_req.result);
+  ASSERT(scandir_req.ptr);
+  while (UV_EOF != uv_fs_scandir_next(&scandir_req, &dent)) {
+    ASSERT(strcmp(dent.name, "file1") == 0 || strcmp(dent.name, "file2") == 0);
+    assert_is_file_type(dent);
+  }
+  uv_fs_req_cleanup(&scandir_req);
+  ASSERT(!scandir_req.ptr);
+
+  /* unlink will remove the directory symlink */
+  r = uv_fs_unlink(NULL, &req, "test_dir_symlink", NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir_symlink", 0, NULL);
+  ASSERT_EQ(r, UV_ENOENT);
+  uv_fs_req_cleanup(&scandir_req);
+
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir", 0, NULL);
+  ASSERT_EQ(2, r);
+  ASSERT_EQ(2, scandir_req.result);
+  ASSERT(scandir_req.ptr);
+  while (UV_EOF != uv_fs_scandir_next(&scandir_req, &dent)) {
+    ASSERT(strcmp(dent.name, "file1") == 0 || strcmp(dent.name, "file2") == 0);
+    assert_is_file_type(dent);
+  }
+  uv_fs_req_cleanup(&scandir_req);
+  ASSERT(!scandir_req.ptr);
+
+  /* clean-up */
+  unlink("test_dir/file1");
+  unlink("test_dir/file2");
+  rmdir("test_dir");
+  rmdir("test_dir_symlink");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_symlink_dir) {
+  return test_symlink_dir_impl(UV_FS_SYMLINK_DIR);
+}
+
+TEST_IMPL(fs_symlink_junction) {
+  return test_symlink_dir_impl(UV_FS_SYMLINK_JUNCTION);
+}
+
+#ifdef _WIN32
+TEST_IMPL(fs_non_symlink_reparse_point) {
+  uv_fs_t req;
+  int r;
+  HANDLE file_handle;
+  REPARSE_GUID_DATA_BUFFER reparse_buffer;
+  DWORD bytes_returned;
+  uv_dirent_t dent;
+
+  /* set-up */
+  unlink("test_dir/test_file");
+  rmdir("test_dir");
+
+  loop = uv_default_loop();
+
+  uv_fs_mkdir(NULL, &req, "test_dir", 0777, NULL);
+  uv_fs_req_cleanup(&req);
+
+  file_handle = CreateFile("test_dir/test_file",
+                           GENERIC_WRITE | FILE_WRITE_ATTRIBUTES,
+                           0,
+                           NULL,
+                           CREATE_ALWAYS,
+                           FILE_FLAG_OPEN_REPARSE_POINT |
+                             FILE_FLAG_BACKUP_SEMANTICS,
+                           NULL);
+  ASSERT_PTR_NE(file_handle, INVALID_HANDLE_VALUE);
+
+  memset(&reparse_buffer, 0, REPARSE_GUID_DATA_BUFFER_HEADER_SIZE);
+  reparse_buffer.ReparseTag = REPARSE_TAG;
+  reparse_buffer.ReparseDataLength = 0;
+  reparse_buffer.ReparseGuid = REPARSE_GUID;
+
+  r = DeviceIoControl(file_handle,
+                      FSCTL_SET_REPARSE_POINT,
+                      &reparse_buffer,
+                      REPARSE_GUID_DATA_BUFFER_HEADER_SIZE,
+                      NULL,
+                      0,
+                      &bytes_returned,
+                      NULL);
+  ASSERT(r);
+
+  CloseHandle(file_handle);
+
+  r = uv_fs_readlink(NULL, &req, "test_dir/test_file", NULL);
+  ASSERT(r == UV_EINVAL && GetLastError() == ERROR_SYMLINK_NOT_SUPPORTED);
+  uv_fs_req_cleanup(&req);
+
+/*
+  Placeholder tests for exercising the behavior fixed in issue #995.
+  To run, update the path with the IP address of a Mac with the hard drive
+  shared via SMB as "Macintosh HD".
+
+  r = uv_fs_stat(NULL, &req, "\\\\<mac_ip>\\Macintosh HD\\.DS_Store", NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_lstat(NULL, &req, "\\\\<mac_ip>\\Macintosh HD\\.DS_Store", NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+*/
+
+/*
+  uv_fs_stat and uv_fs_lstat can only work on non-symlink reparse
+  points when a minifilter driver is registered which intercepts
+  associated filesystem requests. Installing a driver is beyond
+  the scope of this test.
+
+  r = uv_fs_stat(NULL, &req, "test_dir/test_file", NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_lstat(NULL, &req, "test_dir/test_file", NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&req);
+*/
+
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir", 0, NULL);
+  ASSERT_EQ(1, r);
+  ASSERT_EQ(1, scandir_req.result);
+  ASSERT(scandir_req.ptr);
+  while (UV_EOF != uv_fs_scandir_next(&scandir_req, &dent)) {
+    ASSERT_OK(strcmp(dent.name, "test_file"));
+    /* uv_fs_scandir incorrectly identifies non-symlink reparse points
+       as links because it doesn't open the file and verify the reparse
+       point tag. The PowerShell Get-ChildItem command shares this
+       behavior, so it's reasonable to leave it as is. */
+    ASSERT_EQ(dent.type, UV_DIRENT_LINK);
+  }
+  uv_fs_req_cleanup(&scandir_req);
+  ASSERT(!scandir_req.ptr);
+
+  /* clean-up */
+  unlink("test_dir/test_file");
+  rmdir("test_dir");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_lstat_windows_store_apps) {
+  uv_loop_t* loop;
+  char localappdata[MAX_PATH];
+  char windowsapps_path[MAX_PATH];
+  char file_path[MAX_PATH];
+  size_t len;
+  int r;
+  uv_fs_t req;
+  uv_fs_t stat_req;
+  uv_dirent_t dirent;
+
+  loop = uv_default_loop();
+  ASSERT_NOT_NULL(loop);
+  len = sizeof(localappdata);
+  r = uv_os_getenv("LOCALAPPDATA", localappdata, &len);
+  if (r == UV_ENOENT) {
+    MAKE_VALGRIND_HAPPY(loop);
+    return TEST_SKIP;
+  }
+  ASSERT_OK(r);
+  r = snprintf(windowsapps_path,
+              sizeof(localappdata),
+              "%s\\Microsoft\\WindowsApps",
+              localappdata);
+  ASSERT_GT(r, 0);
+  if (uv_fs_opendir(loop, &req, windowsapps_path, NULL) != 0) {
+    /* If we cannot read the directory, skip the test. */
+    MAKE_VALGRIND_HAPPY(loop);
+    return TEST_SKIP;
+  }
+  if (uv_fs_scandir(loop, &req, windowsapps_path, 0, NULL) <= 0) {
+    MAKE_VALGRIND_HAPPY(loop);
+    return TEST_SKIP;
+  }
+  while (uv_fs_scandir_next(&req, &dirent) != UV_EOF) {
+    if (dirent.type != UV_DIRENT_LINK) {
+      continue;
+    }
+    if (snprintf(file_path,
+                 sizeof(file_path),
+                 "%s\\%s",
+                 windowsapps_path,
+                 dirent.name) < 0) {
+      continue;
+    }
+    ASSERT_OK(uv_fs_lstat(loop, &stat_req, file_path, NULL));
+  }
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+#endif
+
+
+TEST_IMPL(fs_utime) {
+  utime_check_t checkme;
+  const char* path = "test_file";
+  double atime;
+  double mtime;
+  uv_fs_t req;
+  int r;
+
+  /* Setup. */
+  loop = uv_default_loop();
+  unlink(path);
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  uv_fs_req_cleanup(&req);
+  uv_fs_close(loop, &req, r, NULL);
+
+  atime = mtime = 400497753.25; /* 1982-09-10 11:22:33.25 */
+
+  ASSERT_OK(uv_fs_utime(NULL, &req, path, atime, mtime, NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_utime(NULL,
+                        &req,
+                        path,
+                        UV_FS_UTIME_OMIT,
+                        UV_FS_UTIME_OMIT,
+                        NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_utime(NULL,
+                        &req,
+                        path,
+                        UV_FS_UTIME_NOW,
+                        UV_FS_UTIME_OMIT,
+                        NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, UV_FS_UTIME_NOW, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_utime(NULL, &req, path, atime, mtime, NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_utime(NULL,
+                        &req,
+                        path,
+                        UV_FS_UTIME_OMIT,
+                        UV_FS_UTIME_NOW,
+                        NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, UV_FS_UTIME_NOW, /* test_lutime */ 0);
+
+  atime = mtime = 1291404900.25; /* 2010-12-03 20:35:00.25 - mees <3 */
+  checkme.path = path;
+  checkme.atime = atime;
+  checkme.mtime = mtime;
+
+  /* async utime */
+  utime_req.data = &checkme;
+  r = uv_fs_utime(loop, &utime_req, path, atime, mtime, utime_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, utime_cb_count);
+
+  /* Cleanup. */
+  unlink(path);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_utime_round) {
+  const char path[] = "test_file";
+  double atime;
+  double mtime;
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+  unlink(path);
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  uv_fs_req_cleanup(&req);
+  ASSERT_OK(uv_fs_close(loop, &req, r, NULL));
+
+  atime = mtime = -14245440.25;  /* 1969-07-20T02:56:00.25Z */
+
+  r = uv_fs_utime(NULL, &req, path, atime, mtime, NULL);
+#if !defined(__linux__)     && \
+    !defined(_WIN32)        && \
+    !defined(__APPLE__)     && \
+    !defined(__FreeBSD__)   && \
+    !defined(__sun)
+  if (r != 0) {
+    ASSERT_EQ(r, UV_EINVAL);
+    RETURN_SKIP("utime on some OS (z/OS, IBM i PASE, AIX) or filesystems may reject pre-epoch timestamps");
+  }
+#endif
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+  unlink(path);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+#ifdef _WIN32
+TEST_IMPL(fs_stat_root) {
+  int r;
+
+  r = uv_fs_stat(NULL, &stat_req, "\\", NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_stat(NULL, &stat_req, "..\\..\\..\\..\\..\\..\\..", NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_stat(NULL, &stat_req, "..", NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_stat(NULL, &stat_req, "..\\", NULL);
+  ASSERT_OK(r);
+
+  /* stats the current directory on c: */
+  r = uv_fs_stat(NULL, &stat_req, "c:", NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_stat(NULL, &stat_req, "c:\\", NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_stat(NULL, &stat_req, "\\\\?\\C:\\", NULL);
+  ASSERT_OK(r);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+#endif
+
+
+TEST_IMPL(fs_futime) {
+  utime_check_t checkme;
+  const char* path = "test_file";
+  double atime;
+  double mtime;
+  uv_file file;
+  uv_fs_t req;
+  int r;
+#if defined(_AIX) && !defined(_AIX71)
+  RETURN_SKIP("futime is not implemented for AIX versions below 7.1");
+#endif
+
+  /* Setup. */
+  loop = uv_default_loop();
+  unlink(path);
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  uv_fs_req_cleanup(&req);
+  uv_fs_close(loop, &req, r, NULL);
+
+  atime = mtime = 400497753.25; /* 1982-09-10 11:22:33.25 */
+
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDWR, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  file = req.result; /* FIXME probably not how it's supposed to be used */
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_futime(NULL, &req, file, atime, mtime, NULL);
+#if defined(__CYGWIN__) || defined(__MSYS__)
+  ASSERT_EQ(r, UV_ENOSYS);
+  RETURN_SKIP("futime not supported on Cygwin");
+#else
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+#endif
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_futime(NULL,
+                         &req,
+                         file,
+                         UV_FS_UTIME_OMIT,
+                         UV_FS_UTIME_OMIT,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_futime(NULL,
+                         &req,
+                         file,
+                         UV_FS_UTIME_NOW,
+                         UV_FS_UTIME_OMIT,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, UV_FS_UTIME_NOW, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_futime(NULL, &req, file, atime, mtime, NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, mtime, /* test_lutime */ 0);
+
+  ASSERT_OK(uv_fs_futime(NULL,
+                         &req,
+                         file,
+                         UV_FS_UTIME_OMIT,
+                         UV_FS_UTIME_NOW,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(path, atime, UV_FS_UTIME_NOW, /* test_lutime */ 0);
+
+  atime = mtime = 1291404900; /* 2010-12-03 20:35:00 - mees <3 */
+
+  checkme.atime = atime;
+  checkme.mtime = mtime;
+  checkme.path = path;
+
+  /* async futime */
+  futime_req.data = &checkme;
+  r = uv_fs_futime(loop, &futime_req, file, atime, mtime, futime_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, futime_cb_count);
+
+  /* Cleanup. */
+  unlink(path);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_lutime) {
+  utime_check_t checkme;
+  const char* path = "test_file";
+  const char* symlink_path = "test_file_symlink";
+  double atime;
+  double mtime;
+  uv_fs_t req;
+  int r, s;
+
+
+  /* Setup */
+  loop = uv_default_loop();
+  unlink(path);
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  uv_fs_req_cleanup(&req);
+  uv_fs_close(loop, &req, r, NULL);
+
+  unlink(symlink_path);
+  s = uv_fs_symlink(NULL, &req, path, symlink_path, 0, NULL);
+#ifdef _WIN32
+  if (s == UV_EPERM) {
+    /*
+     * Creating a symlink before Windows 10 Creators Update was only allowed
+     * when running elevated console (with admin rights)
+     */
+    RETURN_SKIP(
+        "Symlink creation requires elevated console (with admin rights)");
+  }
+#endif
+  ASSERT_OK(s);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+
+  /* Test the synchronous version. */
+  atime = mtime = 400497753.25; /* 1982-09-10 11:22:33.25 */
+
+  r = uv_fs_lutime(NULL, &req, symlink_path, atime, mtime, NULL);
+#if (defined(_AIX) && !defined(_AIX71)) || defined(__MVS__)
+  ASSERT_EQ(r, UV_ENOSYS);
+  RETURN_SKIP("lutime is not implemented for z/OS and AIX versions below 7.1");
+#endif
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(symlink_path, atime, mtime, /* test_lutime */ 1);
+
+  ASSERT_OK(uv_fs_lutime(NULL,
+                         &req,
+                         symlink_path,
+                         UV_FS_UTIME_OMIT,
+                         UV_FS_UTIME_OMIT,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(symlink_path, atime, mtime, /* test_lutime */ 1);
+
+  ASSERT_OK(uv_fs_lutime(NULL,
+                         &req,
+                         symlink_path,
+                         UV_FS_UTIME_NOW,
+                         UV_FS_UTIME_OMIT,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(symlink_path, UV_FS_UTIME_NOW, mtime, /* test_lutime */ 1);
+
+  ASSERT_OK(uv_fs_lutime(NULL, &req, symlink_path, atime, mtime, NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(symlink_path, atime, mtime, /* test_lutime */ 1);
+
+  ASSERT_OK(uv_fs_lutime(NULL,
+                         &req,
+                         symlink_path,
+                         UV_FS_UTIME_OMIT,
+                         UV_FS_UTIME_NOW,
+                         NULL));
+  ASSERT_OK(req.result);
+  uv_fs_req_cleanup(&req);
+  check_utime(symlink_path, atime, UV_FS_UTIME_NOW, /* test_lutime */ 1);
+
+  /* Test the asynchronous version. */
+  atime = mtime = 1291404900; /* 2010-12-03 20:35:00 */
+
+  checkme.atime = atime;
+  checkme.mtime = mtime;
+  checkme.path = symlink_path;
+  req.data = &checkme;
+
+  r = uv_fs_lutime(loop, &req, symlink_path, atime, mtime, lutime_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, lutime_cb_count);
+
+  /* Cleanup. */
+  unlink(path);
+  unlink(symlink_path);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_stat_missing_path) {
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+
+  r = uv_fs_stat(NULL, &req, "non_existent_file", NULL);
+  ASSERT_EQ(r, UV_ENOENT);
+  ASSERT_EQ(req.result, UV_ENOENT);
+  uv_fs_req_cleanup(&req);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_scandir_empty_dir) {
+  const char* path;
+  uv_fs_t req;
+  uv_dirent_t dent;
+  int r;
+
+  path = "./empty_dir/";
+  loop = uv_default_loop();
+
+  uv_fs_mkdir(NULL, &req, path, 0777, NULL);
+  uv_fs_req_cleanup(&req);
+
+  /* Fill the req to ensure that required fields are cleaned up */
+  memset(&req, 0xdb, sizeof(req));
+
+  r = uv_fs_scandir(NULL, &req, path, 0, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(req.result);
+  ASSERT_NULL(req.ptr);
+  ASSERT_EQ(UV_EOF, uv_fs_scandir_next(&req, &dent));
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_scandir(loop, &scandir_req, path, 0, empty_scandir_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(scandir_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, scandir_cb_count);
+
+  uv_fs_rmdir(NULL, &req, path, NULL);
+  uv_fs_req_cleanup(&req);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(fs_scandir_non_existent_dir) {
+  const char* path;
+  uv_fs_t req;
+  uv_dirent_t dent;
+  int r;
+
+  path = "./non_existent_dir/";
+  loop = uv_default_loop();
+
+  uv_fs_rmdir(NULL, &req, path, NULL);
+  uv_fs_req_cleanup(&req);
+
+  /* Fill the req to ensure that required fields are cleaned up */
+  memset(&req, 0xdb, sizeof(req));
+
+  r = uv_fs_scandir(NULL, &req, path, 0, NULL);
+  ASSERT_EQ(r, UV_ENOENT);
+  ASSERT_EQ(req.result, UV_ENOENT);
+  ASSERT_NULL(req.ptr);
+  ASSERT_EQ(UV_ENOENT, uv_fs_scandir_next(&req, &dent));
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_scandir(loop, &scandir_req, path, 0, non_existent_scandir_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(scandir_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, scandir_cb_count);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_scandir_file) {
+  const char* path;
+  int r;
+
+  path = "test/fixtures/empty_file";
+  loop = uv_default_loop();
+
+  r = uv_fs_scandir(NULL, &scandir_req, path, 0, NULL);
+  ASSERT_EQ(r, UV_ENOTDIR);
+  uv_fs_req_cleanup(&scandir_req);
+
+  r = uv_fs_scandir(loop, &scandir_req, path, 0, file_scandir_cb);
+  ASSERT_OK(r);
+
+  ASSERT_OK(scandir_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, scandir_cb_count);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+/* Run in Valgrind. Should not leak when the iterator isn't exhausted. */
+TEST_IMPL(fs_scandir_early_exit) {
+  uv_dirent_t d;
+  uv_fs_t req;
+
+  ASSERT_LT(0, uv_fs_scandir(NULL, &req, "test/fixtures/one_file", 0, NULL));
+  ASSERT_NE(UV_EOF, uv_fs_scandir_next(&req, &d));
+  uv_fs_req_cleanup(&req);
+
+  ASSERT_LT(0, uv_fs_scandir(NULL, &req, "test/fixtures", 0, NULL));
+  ASSERT_NE(UV_EOF, uv_fs_scandir_next(&req, &d));
+  uv_fs_req_cleanup(&req);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+TEST_IMPL(fs_open_dir) {
+  const char* path;
+  uv_fs_t req;
+  int r, file;
+
+  path = ".";
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &req, path, UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(req.result, 0);
+  ASSERT_NULL(req.ptr);
+  file = r;
+  uv_fs_req_cleanup(&req);
+
+  r = uv_fs_close(NULL, &req, file, NULL);
+  ASSERT_OK(r);
+
+  r = uv_fs_open(loop, &req, path, UV_FS_O_RDONLY, 0, open_cb_simple);
+  ASSERT_OK(r);
+
+  ASSERT_OK(open_cb_count);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, open_cb_count);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static void fs_file_open_append(int add_flags) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &open_req1, "test_file",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT | add_flags, S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_APPEND | add_flags, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDONLY | add_flags,
+      S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  printf("read = %d\n", r);
+  ASSERT_EQ(26, r);
+  ASSERT_EQ(26, read_req.result);
+  ASSERT_OK(memcmp(buf,
+                   "test-buffer\n\0test-buffer\n\0",
+                   sizeof("test-buffer\n\0test-buffer\n\0") - 1));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+}
+TEST_IMPL(fs_file_open_append) {
+  fs_file_open_append(0);
+  fs_file_open_append(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+TEST_IMPL(fs_rename_to_existing_file) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+  unlink("test_file2");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file2", UV_FS_O_WRONLY | UV_FS_O_CREAT,
+      S_IWUSR | S_IRUSR, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_rename(NULL, &rename_req, "test_file", "test_file2", NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(rename_req.result);
+  uv_fs_req_cleanup(&rename_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file2", UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(read_req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+  unlink("test_file2");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+static void fs_read_bufs(int add_flags) {
+  char scratch[768];
+  uv_buf_t bufs[4];
+
+  ASSERT_LE(0, uv_fs_open(NULL, &open_req1,
+                          "test/fixtures/lorem_ipsum.txt",
+                          UV_FS_O_RDONLY | add_flags, 0, NULL));
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  ASSERT_EQ(UV_EINVAL, uv_fs_read(NULL, &read_req, open_req1.result,
+                                  NULL, 0, 0, NULL));
+  ASSERT_EQ(UV_EINVAL, uv_fs_read(NULL, &read_req, open_req1.result,
+                                  NULL, 1, 0, NULL));
+  ASSERT_EQ(UV_EINVAL, uv_fs_read(NULL, &read_req, open_req1.result,
+                                  bufs, 0, 0, NULL));
+
+  bufs[0] = uv_buf_init(scratch + 0, 256);
+  bufs[1] = uv_buf_init(scratch + 256, 256);
+  bufs[2] = uv_buf_init(scratch + 512, 128);
+  bufs[3] = uv_buf_init(scratch + 640, 128);
+
+  ASSERT_EQ(446, uv_fs_read(NULL,
+                            &read_req,
+                            open_req1.result,
+                            bufs + 0,
+                            2,  /* 2x 256 bytes. */
+                            0,  /* Positional read. */
+                            NULL));
+  ASSERT_EQ(446, read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  ASSERT_EQ(190, uv_fs_read(NULL,
+                            &read_req,
+                            open_req1.result,
+                            bufs + 2,
+                            2,  /* 2x 128 bytes. */
+                            256,  /* Positional read. */
+                            NULL));
+  ASSERT_EQ(read_req.result, /* 446 - 256 */ 190);
+  uv_fs_req_cleanup(&read_req);
+
+  ASSERT_OK(memcmp(bufs[1].base + 0, bufs[2].base, 128));
+  ASSERT_OK(memcmp(bufs[1].base + 128, bufs[3].base, 190 - 128));
+
+  ASSERT_OK(uv_fs_close(NULL, &close_req, open_req1.result, NULL));
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+}
+TEST_IMPL(fs_read_bufs) {
+  fs_read_bufs(0);
+  fs_read_bufs(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+static void fs_read_file_eof(int add_flags) {
+#if defined(__CYGWIN__) || defined(__MSYS__)
+  RETURN_SKIP("Cygwin pread at EOF may (incorrectly) return data!");
+#endif
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &open_req1, "test_file",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT | add_flags, S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDONLY | add_flags, 0,
+      NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  memset(buf, 0, sizeof(buf));
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(read_req.result, 0);
+  ASSERT_OK(strcmp(buf, test_buf));
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1,
+                 read_req.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+}
+TEST_IMPL(fs_read_file_eof) {
+  fs_read_file_eof(0);
+  fs_read_file_eof(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+static void fs_write_multiple_bufs(int add_flags) {
+  uv_buf_t iovs[2];
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL, &open_req1, "test_file",
+                 UV_FS_O_WRONLY | UV_FS_O_CREAT | add_flags, S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iovs[0] = uv_buf_init(test_buf, sizeof(test_buf));
+  iovs[1] = uv_buf_init(test_buf2, sizeof(test_buf2));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, iovs, 2, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(write_req.result, 0);
+  uv_fs_req_cleanup(&write_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDONLY | add_flags, 0,
+      NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  memset(buf, 0, sizeof(buf));
+  memset(buf2, 0, sizeof(buf2));
+  /* Read the strings back to separate buffers. */
+  iovs[0] = uv_buf_init(buf, sizeof(test_buf));
+  iovs[1] = uv_buf_init(buf2, sizeof(test_buf2));
+  ASSERT_OK(lseek(open_req1.result, 0, SEEK_CUR));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, iovs, 2, -1, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_EQ(read_req.result, sizeof(test_buf) + sizeof(test_buf2));
+  ASSERT_OK(strcmp(buf, test_buf));
+  ASSERT_OK(strcmp(buf2, test_buf2));
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  /* Read the strings back to separate buffers. */
+  iovs[0] = uv_buf_init(buf, sizeof(test_buf));
+  iovs[1] = uv_buf_init(buf2, sizeof(test_buf2));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, iovs, 2, 0, NULL);
+  ASSERT_GE(r, 0);
+  if (read_req.result == sizeof(test_buf)) {
+    /* Infer that preadv is not available. */
+    uv_fs_req_cleanup(&read_req);
+    r = uv_fs_read(NULL, &read_req, open_req1.result, &iovs[1], 1, read_req.result, NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_EQ(read_req.result, sizeof(test_buf2));
+  } else {
+    ASSERT_EQ(read_req.result, sizeof(test_buf) + sizeof(test_buf2));
+  }
+  ASSERT_OK(strcmp(buf, test_buf));
+  ASSERT_OK(strcmp(buf2, test_buf2));
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1,
+                 sizeof(test_buf) + sizeof(test_buf2), NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+}
+TEST_IMPL(fs_write_multiple_bufs) {
+  fs_write_multiple_bufs(0);
+  fs_write_multiple_bufs(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+static void fs_write_alotof_bufs(int add_flags) {
+  size_t iovcount;
+  size_t iovmax;
+  uv_buf_t* iovs;
+  char* buffer;
+  size_t index;
+  int r;
+
+  iovcount = 54321;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  iovs = malloc(sizeof(*iovs) * iovcount);
+  ASSERT_NOT_NULL(iovs);
+  iovmax = uv_test_getiovmax();
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_CREAT | add_flags,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  for (index = 0; index < iovcount; ++index)
+    iovs[index] = uv_buf_init(test_buf, sizeof(test_buf));
+
+  r = uv_fs_write(NULL,
+                  &write_req,
+                  open_req1.result,
+                  iovs,
+                  iovcount,
+                  -1,
+                  NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_EQ((size_t)write_req.result, sizeof(test_buf) * iovcount);
+  uv_fs_req_cleanup(&write_req);
+
+  /* Read the strings back to separate buffers. */
+  buffer = malloc(sizeof(test_buf) * iovcount);
+  ASSERT_NOT_NULL(buffer);
+
+  for (index = 0; index < iovcount; ++index)
+    iovs[index] = uv_buf_init(buffer + index * sizeof(test_buf),
+                              sizeof(test_buf));
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDONLY | add_flags, 0,
+    NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  r = uv_fs_read(NULL, &read_req, open_req1.result, iovs, iovcount, -1, NULL);
+  if (iovcount > iovmax)
+    iovcount = iovmax;
+  ASSERT_GE(r, 0);
+  ASSERT_EQ((size_t)read_req.result, sizeof(test_buf) * iovcount);
+
+  for (index = 0; index < iovcount; ++index)
+    ASSERT_OK(strncmp(buffer + index * sizeof(test_buf),
+                      test_buf,
+                      sizeof(test_buf)));
+
+  uv_fs_req_cleanup(&read_req);
+  free(buffer);
+
+  ASSERT_EQ(lseek(open_req1.result, write_req.result, SEEK_SET),
+            write_req.result);
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL,
+                 &read_req,
+                 open_req1.result,
+                 &iov,
+                 1,
+                 -1,
+                 NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+  free(iovs);
+}
+TEST_IMPL(fs_write_alotof_bufs) {
+  fs_write_alotof_bufs(0);
+  fs_write_alotof_bufs(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+
+static void fs_write_alotof_bufs_with_offset(int add_flags) {
+  size_t iovcount;
+  size_t iovmax;
+  uv_buf_t* iovs;
+  char* buffer;
+  size_t index;
+  int r;
+  int64_t offset;
+  char* filler;
+  int filler_len;
+
+  filler = "0123456789";
+  filler_len = strlen(filler);
+  iovcount = 54321;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  iovs = malloc(sizeof(*iovs) * iovcount);
+  ASSERT_NOT_NULL(iovs);
+  iovmax = uv_test_getiovmax();
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_CREAT | add_flags,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(filler, filler_len);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, filler_len);
+  ASSERT_EQ(write_req.result, filler_len);
+  uv_fs_req_cleanup(&write_req);
+  offset = (int64_t)r;
+
+  for (index = 0; index < iovcount; ++index)
+    iovs[index] = uv_buf_init(test_buf, sizeof(test_buf));
+
+  r = uv_fs_write(NULL,
+                  &write_req,
+                  open_req1.result,
+                  iovs,
+                  iovcount,
+                  offset,
+                  NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_EQ((size_t)write_req.result, sizeof(test_buf) * iovcount);
+  uv_fs_req_cleanup(&write_req);
+
+  /* Read the strings back to separate buffers. */
+  buffer = malloc(sizeof(test_buf) * iovcount);
+  ASSERT_NOT_NULL(buffer);
+
+  for (index = 0; index < iovcount; ++index)
+    iovs[index] = uv_buf_init(buffer + index * sizeof(test_buf),
+                              sizeof(test_buf));
+
+  r = uv_fs_read(NULL, &read_req, open_req1.result,
+                 iovs, iovcount, offset, NULL);
+  ASSERT_GE(r, 0);
+  if (r == sizeof(test_buf))
+    iovcount = 1; /* Infer that preadv is not available. */
+  else if (iovcount > iovmax)
+    iovcount = iovmax;
+  ASSERT_EQ((size_t)read_req.result, sizeof(test_buf) * iovcount);
+
+  for (index = 0; index < iovcount; ++index)
+    ASSERT_OK(strncmp(buffer + index * sizeof(test_buf),
+                      test_buf,
+                      sizeof(test_buf)));
+
+  uv_fs_req_cleanup(&read_req);
+  free(buffer);
+
+  r = uv_fs_stat(NULL, &stat_req, "test_file", NULL);
+  ASSERT_OK(r);
+  ASSERT_EQ((int64_t)((uv_stat_t*)stat_req.ptr)->st_size,
+            offset + (int64_t)write_req.result);
+  uv_fs_req_cleanup(&stat_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL,
+                 &read_req,
+                 open_req1.result,
+                 &iov,
+                 1,
+                 offset + write_req.result,
+                 NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(read_req.result);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+  free(iovs);
+}
+TEST_IMPL(fs_write_alotof_bufs_with_offset) {
+  fs_write_alotof_bufs_with_offset(0);
+  fs_write_alotof_bufs_with_offset(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+TEST_IMPL(fs_read_dir) {
+  int r;
+  char buf[2];
+  loop = uv_default_loop();
+
+  /* Setup */
+  rmdir("test_dir");
+  r = uv_fs_mkdir(loop, &mkdir_req, "test_dir", 0755, mkdir_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(1, mkdir_cb_count);
+  /* Setup Done Here */
+
+  /* Get a file descriptor for the directory */
+  r = uv_fs_open(loop,
+                 &open_req1,
+                 "test_dir",
+                 UV_FS_O_RDONLY | UV_FS_O_DIRECTORY,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  /* Try to read data from the directory */
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, 0, NULL);
+#if defined(__FreeBSD__)   || \
+    defined(__OpenBSD__)   || \
+    defined(__NetBSD__)    || \
+    defined(__DragonFly__) || \
+    defined(_AIX)          || \
+    defined(__sun)         || \
+    defined(__MVS__)
+  /*
+   * As of now, these operating systems support reading from a directory,
+   * that too depends on the filesystem this temporary test directory is
+   * created on. That is why this assertion is a bit lenient.
+   */
+  ASSERT((r >= 0) || (r == UV_EISDIR));
+#else
+  ASSERT_EQ(r, UV_EISDIR);
+#endif
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  rmdir("test_dir");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+#ifdef _WIN32
+
+TEST_IMPL(fs_partial_read) {
+  RETURN_SKIP("Test not implemented on Windows.");
+}
+
+TEST_IMPL(fs_partial_write) {
+  RETURN_SKIP("Test not implemented on Windows.");
+}
+
+#else  /* !_WIN32 */
+
+struct thread_ctx {
+  pthread_t pid;
+  int fd;
+  char* data;
+  int size;
+  int interval;
+  int doread;
+};
+
+static void thread_main(void* arg) {
+  const struct thread_ctx* ctx;
+  int size;
+  char* data;
+
+  ctx = (struct thread_ctx*)arg;
+  size = ctx->size;
+  data = ctx->data;
+
+  while (size > 0) {
+    ssize_t result;
+    int nbytes;
+    nbytes = size < ctx->interval ? size : ctx->interval;
+    if (ctx->doread) {
+      result = write(ctx->fd, data, nbytes);
+      /* Should not see EINTR (or other errors) */
+      ASSERT_EQ(result, nbytes);
+    } else {
+      result = read(ctx->fd, data, nbytes);
+      /* Should not see EINTR (or other errors),
+       * but might get a partial read if we are faster than the writer
+       */
+      ASSERT(result > 0 && result <= nbytes);
+    }
+
+    pthread_kill(ctx->pid, SIGUSR1);
+    size -= result;
+    data += result;
+  }
+}
+
+static void sig_func(uv_signal_t* handle, int signum) {
+  uv_signal_stop(handle);
+}
+
+static size_t uv_test_fs_buf_offset(uv_buf_t* bufs, size_t size) {
+  size_t offset;
+  /* Figure out which bufs are done */
+  for (offset = 0; size > 0 && bufs[offset].len <= size; ++offset)
+    size -= bufs[offset].len;
+
+  /* Fix a partial read/write */
+  if (size > 0) {
+    bufs[offset].base += size;
+    bufs[offset].len -= size;
+  }
+  return offset;
+}
+
+static void test_fs_partial(int doread) {
+  struct thread_ctx ctx;
+  uv_thread_t thread;
+  uv_signal_t signal;
+  int pipe_fds[2];
+  size_t iovcount;
+  uv_buf_t* iovs;
+  char* buffer;
+  size_t index;
+
+  iovcount = 54321;
+
+  iovs = malloc(sizeof(*iovs) * iovcount);
+  ASSERT_NOT_NULL(iovs);
+
+  ctx.pid = pthread_self();
+  ctx.doread = doread;
+  ctx.interval = 1000;
+  ctx.size = sizeof(test_buf) * iovcount;
+  ctx.data = calloc(ctx.size, 1);
+  ASSERT_NOT_NULL(ctx.data);
+  buffer = calloc(ctx.size, 1);
+  ASSERT_NOT_NULL(buffer);
+
+  for (index = 0; index < iovcount; ++index)
+    iovs[index] = uv_buf_init(buffer + index * sizeof(test_buf), sizeof(test_buf));
+
+  loop = uv_default_loop();
+
+  ASSERT_OK(uv_signal_init(loop, &signal));
+  ASSERT_OK(uv_signal_start(&signal, sig_func, SIGUSR1));
+
+  ASSERT_OK(pipe(pipe_fds));
+
+  ctx.fd = pipe_fds[doread];
+  ASSERT_OK(uv_thread_create(&thread, thread_main, &ctx));
+
+  if (doread) {
+    uv_buf_t* read_iovs;
+    int nread;
+    read_iovs = iovs;
+    nread = 0;
+    while (nread < ctx.size) {
+      int result;
+      result = uv_fs_read(loop, &read_req, pipe_fds[0], read_iovs, iovcount, -1, NULL);
+      if (result > 0) {
+        size_t read_iovcount;
+        read_iovcount = uv_test_fs_buf_offset(read_iovs, result);
+        read_iovs += read_iovcount;
+        iovcount -= read_iovcount;
+        nread += result;
+      } else {
+        ASSERT_EQ(result, UV_EINTR);
+      }
+      uv_fs_req_cleanup(&read_req);
+    }
+  } else {
+    int result;
+    result = uv_fs_write(loop, &write_req, pipe_fds[1], iovs, iovcount, -1, NULL);
+    ASSERT_EQ(write_req.result, result);
+    ASSERT_EQ(result, ctx.size);
+    uv_fs_req_cleanup(&write_req);
+  }
+
+  ASSERT_OK(uv_thread_join(&thread));
+
+  ASSERT_MEM_EQ(buffer, ctx.data, ctx.size);
+
+  ASSERT_OK(uv_run(loop, UV_RUN_DEFAULT));
+
+  ASSERT_OK(close(pipe_fds[1]));
+  uv_close((uv_handle_t*) &signal, NULL);
+
+  { /* Make sure we read everything that we wrote. */
+      int result;
+      result = uv_fs_read(loop, &read_req, pipe_fds[0], iovs, 1, -1, NULL);
+      ASSERT_OK(result);
+      uv_fs_req_cleanup(&read_req);
+  }
+  ASSERT_OK(close(pipe_fds[0]));
+
+  free(iovs);
+  free(buffer);
+  free(ctx.data);
+
+  MAKE_VALGRIND_HAPPY(loop);
+}
+
+TEST_IMPL(fs_partial_read) {
+  test_fs_partial(1);
+  return 0;
+}
+
+TEST_IMPL(fs_partial_write) {
+  test_fs_partial(0);
+  return 0;
+}
+
+#endif/* _WIN32 */
+
+TEST_IMPL(fs_read_write_null_arguments) {
+  int r;
+
+  r = uv_fs_read(NULL, &read_req, 0, NULL, 0, -1, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_write(NULL, &write_req, 0, NULL, 0, -1, NULL);
+  /* Validate some memory management on failed input validation before sending
+     fs work to the thread pool. */
+  ASSERT_EQ(r, UV_EINVAL);
+  ASSERT_NULL(write_req.path);
+  ASSERT_NULL(write_req.ptr);
+#ifdef _WIN32
+  ASSERT_NULL(write_req.file.pathw);
+  ASSERT_NULL(write_req.fs.info.new_pathw);
+  ASSERT_NULL(write_req.fs.info.bufs);
+#else
+  ASSERT_NULL(write_req.new_path);
+  ASSERT_NULL(write_req.bufs);
+#endif
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(NULL, 0);
+  r = uv_fs_read(NULL, &read_req, 0, &iov, 0, -1, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(NULL, 0);
+  r = uv_fs_write(NULL, &write_req, 0, &iov, 0, -1, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_fs_req_cleanup(&write_req);
+
+  /* If the arguments are invalid, the loop should not be kept open */
+  loop = uv_default_loop();
+
+  r = uv_fs_read(loop, &read_req, 0, NULL, 0, -1, fail_cb);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_run(loop, UV_RUN_DEFAULT);
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_write(loop, &write_req, 0, NULL, 0, -1, fail_cb);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_run(loop, UV_RUN_DEFAULT);
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(NULL, 0);
+  r = uv_fs_read(loop, &read_req, 0, &iov, 0, -1, fail_cb);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_run(loop, UV_RUN_DEFAULT);
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(NULL, 0);
+  r = uv_fs_write(loop, &write_req, 0, &iov, 0, -1, fail_cb);
+  ASSERT_EQ(r, UV_EINVAL);
+  uv_run(loop, UV_RUN_DEFAULT);
+  uv_fs_req_cleanup(&write_req);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+TEST_IMPL(get_osfhandle_valid_handle) {
+  int r;
+  uv_os_fd_t fd;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL,
+                 &open_req1, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  fd = uv_get_osfhandle(open_req1.result);
+#ifdef _WIN32
+  ASSERT_PTR_NE(fd, INVALID_HANDLE_VALUE);
+#else
+  ASSERT_GE(fd, 0);
+#endif
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup. */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(open_osfhandle_valid_handle) {
+  int r;
+  uv_os_fd_t handle;
+  int fd;
+
+  /* Setup. */
+  unlink("test_file");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  handle = uv_get_osfhandle(open_req1.result);
+#ifdef _WIN32
+  ASSERT_PTR_NE(handle, INVALID_HANDLE_VALUE);
+#else
+  ASSERT_GE(handle, 0);
+#endif
+
+  fd = uv_open_osfhandle(handle);
+#ifdef _WIN32
+  ASSERT_GT(fd, 0);
+#else
+  ASSERT_EQ(fd, open_req1.result);
+#endif
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup. */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_file_pos_after_op_with_offset) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+  loop = uv_default_loop();
+
+  r = uv_fs_open(loop,
+                 &open_req1, "test_file", UV_FS_O_RDWR | UV_FS_O_CREAT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GT(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(test_buf, sizeof(test_buf));
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, 0, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_OK(lseek(open_req1.result, 0, SEEK_CUR));
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, 0, NULL);
+  ASSERT_EQ(r, sizeof(test_buf));
+  ASSERT_OK(strcmp(buf, test_buf));
+  ASSERT_OK(lseek(open_req1.result, 0, SEEK_CUR));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+#ifdef _WIN32
+static void fs_file_pos_common(void) {
+  int r;
+
+  iov = uv_buf_init("abc", 3);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(3, r);
+  uv_fs_req_cleanup(&write_req);
+
+  /* Read with offset should not change the position */
+  iov = uv_buf_init(buf, 1);
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, 1, NULL);
+  ASSERT_EQ(1, r);
+  ASSERT_EQ(buf[0], 'b');
+  uv_fs_req_cleanup(&read_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&read_req);
+
+  /* Write without offset should change the position */
+  iov = uv_buf_init("d", 1);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(1, r);
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&read_req);
+}
+
+static void fs_file_pos_close_check(const char *contents, int size) {
+  int r;
+
+  /* Close */
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Confirm file contents */
+  r = uv_fs_open(NULL, &open_req1, "test_file", UV_FS_O_RDONLY, 0, NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(r, size);
+  ASSERT_OK(strncmp(buf, contents, size));
+  uv_fs_req_cleanup(&read_req);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+}
+
+static void fs_file_pos_write(int add_flags) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_TRUNC | UV_FS_O_CREAT | UV_FS_O_RDWR | add_flags,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GT(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  fs_file_pos_common();
+
+  /* Write with offset should not change the position */
+  iov = uv_buf_init("e", 1);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, 1, NULL);
+  ASSERT_EQ(1, r);
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&read_req);
+
+  fs_file_pos_close_check("aecd", 4);
+}
+TEST_IMPL(fs_file_pos_write) {
+  fs_file_pos_write(0);
+  fs_file_pos_write(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+
+static void fs_file_pos_append(int add_flags) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_APPEND | UV_FS_O_CREAT | UV_FS_O_RDWR | add_flags,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GT(r, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  fs_file_pos_common();
+
+  /* Write with offset appends (ignoring offset)
+   * but does not change the position */
+  iov = uv_buf_init("e", 1);
+  r = uv_fs_write(NULL, &write_req, open_req1.result, &iov, 1, 1, NULL);
+  ASSERT_EQ(1, r);
+  uv_fs_req_cleanup(&write_req);
+
+  iov = uv_buf_init(buf, sizeof(buf));
+  r = uv_fs_read(NULL, &read_req, open_req1.result, &iov, 1, -1, NULL);
+  ASSERT_EQ(1, r);
+  ASSERT_EQ(buf[0], 'e');
+  uv_fs_req_cleanup(&read_req);
+
+  fs_file_pos_close_check("abcde", 5);
+}
+TEST_IMPL(fs_file_pos_append) {
+  fs_file_pos_append(0);
+  fs_file_pos_append(UV_FS_O_FILEMAP);
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+#endif
+
+TEST_IMPL(fs_null_req) {
+  /* Verify that all fs functions return UV_EINVAL when the request is NULL. */
+  int r;
+
+  r = uv_fs_open(NULL, NULL, NULL, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_close(NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_read(NULL, NULL, 0, NULL, 0, -1, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_write(NULL, NULL, 0, NULL, 0, -1, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_unlink(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_mkdir(NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_mkdtemp(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_mkstemp(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_rmdir(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_scandir(NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_link(NULL, NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_symlink(NULL, NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_readlink(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_realpath(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_chown(NULL, NULL, NULL, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_fchown(NULL, NULL, 0, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_stat(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_lstat(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_fstat(NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_rename(NULL, NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_fsync(NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_fdatasync(NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_ftruncate(NULL, NULL, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_copyfile(NULL, NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_sendfile(NULL, NULL, 0, 0, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_access(NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_chmod(NULL, NULL, NULL, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_fchmod(NULL, NULL, 0, 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_utime(NULL, NULL, NULL, 0.0, 0.0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_futime(NULL, NULL, 0, 0.0, 0.0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  r = uv_fs_statfs(NULL, NULL, NULL, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+
+  /* This should be a no-op. */
+  uv_fs_req_cleanup(NULL);
+
+  return 0;
+}
+
+#ifdef _WIN32
+TEST_IMPL(fs_exclusive_sharing_mode) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  ASSERT_GT(UV_FS_O_EXLOCK, 0);
+
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_CREAT | UV_FS_O_EXLOCK,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  r = uv_fs_open(NULL,
+                 &open_req2,
+                 "test_file", UV_FS_O_RDONLY | UV_FS_O_EXLOCK,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_LT(r, 0);
+  ASSERT_LT(open_req2.result, 0);
+  uv_fs_req_cleanup(&open_req2);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  r = uv_fs_open(NULL,
+                 &open_req2,
+                 "test_file", UV_FS_O_RDONLY | UV_FS_O_EXLOCK,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req2.result, 0);
+  uv_fs_req_cleanup(&open_req2);
+
+  r = uv_fs_close(NULL, &close_req, open_req2.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* Cleanup */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+#endif
+
+#ifdef _WIN32
+TEST_IMPL(fs_file_flag_no_buffering) {
+  int r;
+
+  /* Setup. */
+  unlink("test_file");
+
+  ASSERT_GT(UV_FS_O_APPEND, 0);
+  ASSERT_GT(UV_FS_O_CREAT, 0);
+  ASSERT_GT(UV_FS_O_DIRECT, 0);
+  ASSERT_GT(UV_FS_O_RDWR, 0);
+
+  /* FILE_APPEND_DATA must be excluded from FILE_GENERIC_WRITE: */
+  r = uv_fs_open(NULL,
+                 &open_req1,
+                 "test_file",
+                 UV_FS_O_RDWR | UV_FS_O_CREAT | UV_FS_O_DIRECT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_GE(r, 0);
+  ASSERT_GE(open_req1.result, 0);
+  uv_fs_req_cleanup(&open_req1);
+
+  r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+  ASSERT_OK(r);
+  ASSERT_OK(close_req.result);
+  uv_fs_req_cleanup(&close_req);
+
+  /* FILE_APPEND_DATA and FILE_FLAG_NO_BUFFERING are mutually exclusive: */
+  r = uv_fs_open(NULL,
+                 &open_req2,
+                 "test_file",
+                 UV_FS_O_APPEND | UV_FS_O_DIRECT,
+                 S_IWUSR | S_IRUSR,
+                 NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+  ASSERT_EQ(open_req2.result, UV_EINVAL);
+  uv_fs_req_cleanup(&open_req2);
+
+  /* Cleanup */
+  unlink("test_file");
+
+  MAKE_VALGRIND_HAPPY(uv_default_loop());
+  return 0;
+}
+#endif
+
+#ifdef _WIN32
+int call_icacls(const char* command, ...) {
+    char icacls_command[1024];
+    va_list args;
+
+    va_start(args, command);
+    vsnprintf(icacls_command, ARRAYSIZE(icacls_command), command, args);
+    va_end(args);
+    return system(icacls_command);
+}
+
+TEST_IMPL(fs_open_readonly_acl) {
+    uv_passwd_t pwd;
+    uv_fs_t req;
+    int r;
+
+    /*
+        Based on Node.js test from
+        https://github.com/nodejs/node/commit/3ba81e34e86a5c32658e218cb6e65b13e8326bc5
+
+        If anything goes wrong, you can delte the test_fle_icacls with:
+
+            icacls test_file_icacls /remove "%USERNAME%" /inheritance:e
+            attrib -r test_file_icacls
+            del test_file_icacls
+    */
+
+    /* Setup - clear the ACL and remove the file */
+    loop = uv_default_loop();
+    r = uv_os_get_passwd(&pwd);
+    ASSERT_OK(r);
+    call_icacls("icacls test_file_icacls /remove \"%s\" /inheritance:e",
+                pwd.username);
+    uv_fs_chmod(loop, &req, "test_file_icacls", S_IWUSR, NULL);
+    unlink("test_file_icacls");
+
+    /* Create the file */
+    r = uv_fs_open(loop,
+                   &open_req1,
+                   "test_file_icacls",
+                   UV_FS_O_RDONLY | UV_FS_O_CREAT,
+                   S_IRUSR,
+                   NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(open_req1.result, 0);
+    uv_fs_req_cleanup(&open_req1);
+    r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+    ASSERT_OK(r);
+    ASSERT_OK(close_req.result);
+    uv_fs_req_cleanup(&close_req);
+
+    /* Set up ACL */
+    r = call_icacls("icacls test_file_icacls /inheritance:r /remove \"%s\"",
+                    pwd.username);
+    if (r != 0) {
+        goto acl_cleanup;
+    }
+    r = call_icacls("icacls test_file_icacls /grant \"%s\":RX", pwd.username);
+    if (r != 0) {
+        goto acl_cleanup;
+    }
+
+    /* Try opening the file */
+    r = uv_fs_open(NULL, &open_req1, "test_file_icacls", UV_FS_O_RDONLY, 0,
+                   NULL);
+    if (r < 0) {
+        goto acl_cleanup;
+    }
+    uv_fs_req_cleanup(&open_req1);
+    r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+    if (r != 0) {
+        goto acl_cleanup;
+    }
+    uv_fs_req_cleanup(&close_req);
+
+ acl_cleanup:
+    /* Cleanup */
+    call_icacls("icacls test_file_icacls /remove \"%s\" /inheritance:e",
+                pwd.username);
+    unlink("test_file_icacls");
+    uv_os_free_passwd(&pwd);
+    ASSERT_OK(r);
+    MAKE_VALGRIND_HAPPY(loop);
+    return 0;
+}
+
+TEST_IMPL(fs_stat_no_permission) {
+    uv_passwd_t pwd;
+    uv_fs_t req;
+    int r;
+    char* filename = "test_file_no_permission.txt";
+
+    /* Setup - clear the ACL and remove the file */
+    loop = uv_default_loop();
+    r = uv_os_get_passwd(&pwd);
+    ASSERT_OK(r);
+    call_icacls("icacls %s /remove *S-1-1-0:(F)", filename);
+    unlink(filename);
+
+    /* Create the file */
+    r = uv_fs_open(loop,
+                   &open_req1,
+                   filename,
+                   UV_FS_O_RDONLY | UV_FS_O_CREAT,
+                   S_IRUSR,
+                   NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(open_req1.result, 0);
+    uv_fs_req_cleanup(&open_req1);
+    r = uv_fs_close(NULL, &close_req, open_req1.result, NULL);
+    ASSERT_OK(r);
+    ASSERT_OK(close_req.result);
+    uv_fs_req_cleanup(&close_req);
+
+    /* Set up ACL */
+    r = call_icacls("icacls %s /deny *S-1-1-0:(F)", filename);
+    if (r != 0) {
+        goto acl_cleanup;
+    }
+
+    /* Read file stats */
+    r = uv_fs_stat(NULL, &req, filename, NULL);
+    if (r != 0) {
+        goto acl_cleanup;
+    }
+
+    uv_fs_req_cleanup(&req);
+
+ acl_cleanup:
+    /* Cleanup */
+    call_icacls("icacls %s /reset", filename);
+    uv_fs_unlink(NULL, &unlink_req, filename, NULL);
+    uv_fs_req_cleanup(&unlink_req);
+    unlink(filename);
+    uv_os_free_passwd(&pwd);
+    ASSERT_OK(r);
+    MAKE_VALGRIND_HAPPY(loop);
+    return 0;
+}
+#endif
+
+#ifdef _WIN32
+TEST_IMPL(fs_fchmod_archive_readonly) {
+    uv_fs_t req;
+    uv_file file;
+    int r;
+    /* Test clearing read-only flag from files with Archive flag cleared */
+
+    /* Setup*/
+    unlink("test_file");
+    r = uv_fs_open(NULL,
+                   &req, "test_file", UV_FS_O_WRONLY | UV_FS_O_CREAT,
+                   S_IWUSR | S_IRUSR,
+                   NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(req.result, 0);
+    file = req.result;
+    uv_fs_req_cleanup(&req);
+    r = uv_fs_close(NULL, &req, file, NULL);
+    ASSERT_OK(r);
+    uv_fs_req_cleanup(&req);
+    /* Make the file read-only and clear archive flag */
+    r = SetFileAttributes("test_file", FILE_ATTRIBUTE_READONLY);
+    ASSERT(r);
+    check_permission("test_file", 0400);
+    /* Try fchmod */
+    r = uv_fs_open(NULL, &req, "test_file", UV_FS_O_RDONLY, 0, NULL);
+    ASSERT_GE(r, 0);
+    ASSERT_GE(req.result, 0);
+    file = req.result;
+    uv_fs_req_cleanup(&req);
+    r = uv_fs_fchmod(NULL, &req, file, S_IWUSR, NULL);
+    ASSERT_OK(r);
+    ASSERT_OK(req.result);
+    uv_fs_req_cleanup(&req);
+    r = uv_fs_close(NULL, &req, file, NULL);
+    ASSERT_OK(r);
+    uv_fs_req_cleanup(&req);
+    check_permission("test_file", S_IWUSR);
+
+    /* Restore Archive flag for rest of the tests */
+    r = SetFileAttributes("test_file", FILE_ATTRIBUTE_ARCHIVE);
+    ASSERT(r);
+
+    return 0;
+}
+
+TEST_IMPL(fs_invalid_mkdir_name) {
+  uv_loop_t* loop;
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+  r = uv_fs_mkdir(loop, &req, "invalid>", 0, NULL);
+  ASSERT_EQ(r, UV_EINVAL);
+  ASSERT_EQ(UV_EINVAL, uv_fs_mkdir(loop, &req, "test:lol", 0, NULL));
+
+  return 0;
+}
+#endif
+
+TEST_IMPL(fs_statfs) {
+  uv_fs_t req;
+  int r;
+
+  loop = uv_default_loop();
+
+  /* Test the synchronous version. */
+  r = uv_fs_statfs(NULL, &req, ".", NULL);
+  ASSERT_OK(r);
+  statfs_cb(&req);
+  ASSERT_EQ(1, statfs_cb_count);
+
+  /* Test the asynchronous version. */
+  r = uv_fs_statfs(loop, &req, ".", statfs_cb);
+  ASSERT_OK(r);
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(2, statfs_cb_count);
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+TEST_IMPL(fs_get_system_error) {
+  uv_fs_t req;
+  int r;
+  int system_error;
+
+  r = uv_fs_statfs(NULL, &req, "non_existing_file", NULL);
+  ASSERT(r);
+
+  system_error = uv_fs_get_system_error(&req);
+#ifdef _WIN32
+  ASSERT_EQ(system_error, ERROR_FILE_NOT_FOUND);
+#else
+  ASSERT_EQ(system_error, ENOENT);
+#endif
+
+  return 0;
+}
+
+
+TEST_IMPL(fs_stat_batch_multiple) {
+  uv_fs_t req[300];
+  int r;
+  int i;
+
+  rmdir("test_dir");
+
+  r = uv_fs_mkdir(NULL, &mkdir_req, "test_dir", 0755, NULL);
+  ASSERT_OK(r);
+
+  loop = uv_default_loop();
+
+  for (i = 0; i < (int) ARRAY_SIZE(req); ++i) {
+    r = uv_fs_stat(loop, &req[i], "test_dir", stat_batch_cb);
+    ASSERT_OK(r);
+  }
+
+  uv_run(loop, UV_RUN_DEFAULT);
+  ASSERT_EQ(stat_cb_count, ARRAY_SIZE(req));
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+
+
+#ifdef _WIN32
+TEST_IMPL(fs_wtf) {
+  int r;
+  HANDLE file_handle;
+  uv_dirent_t dent;
+  static char test_file_buf[PATHMAX];
+
+  /* set-up */
+  _wunlink(L"test_dir/hi\xD801\x0037");
+  rmdir("test_dir");
+
+  loop = uv_default_loop();
+
+  r = uv_fs_mkdir(NULL, &mkdir_req, "test_dir", 0777, NULL);
+  ASSERT_OK(r);
+  uv_fs_req_cleanup(&mkdir_req);
+
+  file_handle = CreateFileW(L"test_dir/hi\xD801\x0037",
+                            GENERIC_WRITE | FILE_WRITE_ATTRIBUTES,
+                            0,
+                            NULL,
+                            CREATE_ALWAYS,
+                            FILE_FLAG_OPEN_REPARSE_POINT |
+                              FILE_FLAG_BACKUP_SEMANTICS,
+                            NULL);
+  ASSERT_PTR_NE(file_handle, INVALID_HANDLE_VALUE);
+
+  CloseHandle(file_handle);
+
+  r = uv_fs_scandir(NULL, &scandir_req, "test_dir", 0, NULL);
+  ASSERT_EQ(1, r);
+  ASSERT_EQ(1, scandir_req.result);
+  ASSERT_NOT_NULL(scandir_req.ptr);
+  while (UV_EOF != uv_fs_scandir_next(&scandir_req, &dent)) {
+    snprintf(test_file_buf, sizeof(test_file_buf), "test_dir\\%s", dent.name);
+    printf("stat %s\n", test_file_buf);
+    r = uv_fs_stat(NULL, &stat_req, test_file_buf, NULL);
+    ASSERT_OK(r);
+  }
+  uv_fs_req_cleanup(&scandir_req);
+  ASSERT_NULL(scandir_req.ptr);
+
+  /* clean-up */
+  _wunlink(L"test_dir/hi\xD801\x0037");
+  rmdir("test_dir");
+
+  MAKE_VALGRIND_HAPPY(loop);
+  return 0;
+}
+#endif