--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/src/unix/os390-syscalls.h	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,75 @@
+/* Copyright libuv project 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.
+ */
+
+
+#ifndef UV_OS390_SYSCALL_H_
+#define UV_OS390_SYSCALL_H_
+
+#include "uv.h"
+#include "internal.h"
+#include <dirent.h>
+#include <poll.h>
+#include <pthread.h>
+#include "zos-base.h"
+
+#define EPOLL_CTL_ADD             1
+#define EPOLL_CTL_DEL             2
+#define EPOLL_CTL_MOD             3
+#define MAX_EPOLL_INSTANCES       256
+#define MAX_ITEMS_PER_EPOLL       1024
+
+#define UV__O_CLOEXEC             0x80000
+
+struct epoll_event {
+  int events;
+  int fd;
+  int is_msg;
+};
+
+typedef struct {
+  struct uv__queue member;
+  struct pollfd* items;
+  unsigned long size;
+  int msg_queue;
+} uv__os390_epoll;
+
+/* epoll api */
+uv__os390_epoll* epoll_create1(int flags);
+int epoll_ctl(uv__os390_epoll* ep, int op, int fd, struct epoll_event *event);
+int epoll_wait(uv__os390_epoll* ep, struct epoll_event *events, int maxevents, int timeout);
+int epoll_file_close(int fd);
+
+/* utility functions */
+int scandir(const char* maindir, struct dirent*** namelist,
+            int (*filter)(const struct dirent *),
+            int (*compar)(const struct dirent **,
+            const struct dirent **));
+char *mkdtemp(char* path);
+ssize_t os390_readlink(const char* path, char* buf, size_t len);
+size_t strnlen(const char* str, size_t maxlen);
+int sem_init(UV_PLATFORM_SEM_T* semid, int pshared, unsigned int value);
+int sem_destroy(UV_PLATFORM_SEM_T* semid);
+int sem_post(UV_PLATFORM_SEM_T* semid);
+int sem_trywait(UV_PLATFORM_SEM_T* semid);
+int sem_wait(UV_PLATFORM_SEM_T* semid);
+void uv__os390_cleanup(void);
+
+#endif /* UV_OS390_SYSCALL_H_ */