--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/third_party/libuv/docs/src/errors.rst	Wed Jan 14 19:39:52 2026 -0800
@@ -0,0 +1,388 @@
+
+.. _errors:
+
+Error handling
+==============
+
+In libuv errors are negative numbered constants. As a rule of thumb, whenever
+there is a status parameter, or an API functions returns an integer, a negative
+number will imply an error.
+
+When a function which takes a callback returns an error, the callback will never
+be called.
+
+.. note::
+    Implementation detail: on Unix error codes are the negated `errno` (or `-errno`), while on
+    Windows they are defined by libuv to arbitrary negative numbers.
+
+
+Error constants
+---------------
+
+.. c:macro:: UV_E2BIG
+
+    argument list too long
+
+.. c:macro:: UV_EACCES
+
+    permission denied
+
+.. c:macro:: UV_EADDRINUSE
+
+    address already in use
+
+.. c:macro:: UV_EADDRNOTAVAIL
+
+    address not available
+
+.. c:macro:: UV_EAFNOSUPPORT
+
+    address family not supported
+
+.. c:macro:: UV_EAGAIN
+
+    resource temporarily unavailable
+
+.. c:macro:: UV_EAI_ADDRFAMILY
+
+    address family not supported
+
+.. c:macro:: UV_EAI_AGAIN
+
+    temporary failure
+
+.. c:macro:: UV_EAI_BADFLAGS
+
+    bad ai_flags value
+
+.. c:macro:: UV_EAI_BADHINTS
+
+    invalid value for hints
+
+.. c:macro:: UV_EAI_CANCELED
+
+    request canceled
+
+.. c:macro:: UV_EAI_FAIL
+
+    permanent failure
+
+.. c:macro:: UV_EAI_FAMILY
+
+    ai_family not supported
+
+.. c:macro:: UV_EAI_MEMORY
+
+    out of memory
+
+.. c:macro:: UV_EAI_NODATA
+
+    no address
+
+.. c:macro:: UV_EAI_NONAME
+
+    unknown node or service
+
+.. c:macro:: UV_EAI_OVERFLOW
+
+    argument buffer overflow
+
+.. c:macro:: UV_EAI_PROTOCOL
+
+    resolved protocol is unknown
+
+.. c:macro:: UV_EAI_SERVICE
+
+    service not available for socket type
+
+.. c:macro:: UV_EAI_SOCKTYPE
+
+    socket type not supported
+
+.. c:macro:: UV_EALREADY
+
+    connection already in progress
+
+.. c:macro:: UV_EBADF
+
+    bad file descriptor
+
+.. c:macro:: UV_EBUSY
+
+    resource busy or locked
+
+.. c:macro:: UV_ECANCELED
+
+    operation canceled
+
+.. c:macro:: UV_ECHARSET
+
+    invalid Unicode character
+
+.. c:macro:: UV_ECONNABORTED
+
+    software caused connection abort
+
+.. c:macro:: UV_ECONNREFUSED
+
+    connection refused
+
+.. c:macro:: UV_ECONNRESET
+
+    connection reset by peer
+
+.. c:macro:: UV_EDESTADDRREQ
+
+    destination address required
+
+.. c:macro:: UV_EEXIST
+
+    file already exists
+
+.. c:macro:: UV_EFAULT
+
+    bad address in system call argument
+
+.. c:macro:: UV_EFBIG
+
+    file too large
+
+.. c:macro:: UV_EHOSTUNREACH
+
+    host is unreachable
+
+.. c:macro:: UV_EINTR
+
+    interrupted system call
+
+.. c:macro:: UV_EINVAL
+
+    invalid argument
+
+.. c:macro:: UV_EIO
+
+    i/o error
+
+.. c:macro:: UV_EISCONN
+
+    socket is already connected
+
+.. c:macro:: UV_EISDIR
+
+    illegal operation on a directory
+
+.. c:macro:: UV_ELOOP
+
+    too many symbolic links encountered
+
+.. c:macro:: UV_EMFILE
+
+    too many open files
+
+.. c:macro:: UV_EMSGSIZE
+
+    message too long
+
+.. c:macro:: UV_ENAMETOOLONG
+
+    name too long
+
+.. c:macro:: UV_ENETDOWN
+
+    network is down
+
+.. c:macro:: UV_ENETUNREACH
+
+    network is unreachable
+
+.. c:macro:: UV_ENFILE
+
+    file table overflow
+
+.. c:macro:: UV_ENOBUFS
+
+    no buffer space available
+
+.. c:macro:: UV_ENODEV
+
+    no such device
+
+.. c:macro:: UV_ENOENT
+
+    no such file or directory
+
+.. c:macro:: UV_ENOMEM
+
+    not enough memory
+
+.. c:macro:: UV_ENONET
+
+    machine is not on the network
+
+.. c:macro:: UV_ENOPROTOOPT
+
+    protocol not available
+
+.. c:macro:: UV_ENOSPC
+
+    no space left on device
+
+.. c:macro:: UV_ENOSYS
+
+    function not implemented
+
+.. c:macro:: UV_ENOTCONN
+
+    socket is not connected
+
+.. c:macro:: UV_ENOTDIR
+
+    not a directory
+
+.. c:macro:: UV_ENOTEMPTY
+
+    directory not empty
+
+.. c:macro:: UV_ENOTSOCK
+
+    socket operation on non-socket
+
+.. c:macro:: UV_ENOTSUP
+
+    operation not supported on socket
+
+.. c:macro:: UV_EOVERFLOW
+
+    value too large for defined data type
+
+.. c:macro:: UV_EPERM
+
+    operation not permitted
+
+.. c:macro:: UV_EPIPE
+
+    broken pipe
+
+.. c:macro:: UV_EPROTO
+
+    protocol error
+
+.. c:macro:: UV_EPROTONOSUPPORT
+
+    protocol not supported
+
+.. c:macro:: UV_EPROTOTYPE
+
+    protocol wrong type for socket
+
+.. c:macro:: UV_ERANGE
+
+    result too large
+
+.. c:macro:: UV_EROFS
+
+    read-only file system
+
+.. c:macro:: UV_ESHUTDOWN
+
+    cannot send after transport endpoint shutdown
+
+.. c:macro:: UV_ESPIPE
+
+    invalid seek
+
+.. c:macro:: UV_ESRCH
+
+    no such process
+
+.. c:macro:: UV_ETIMEDOUT
+
+    connection timed out
+
+.. c:macro:: UV_ETXTBSY
+
+    text file is busy
+
+.. c:macro:: UV_EXDEV
+
+    cross-device link not permitted
+
+.. c:macro:: UV_UNKNOWN
+
+    unknown error
+
+.. c:macro:: UV_EOF
+
+    end of file
+
+.. c:macro:: UV_ENXIO
+
+    no such device or address
+
+.. c:macro:: UV_EMLINK
+
+    too many links
+
+.. c:macro:: UV_ENOTTY
+
+    inappropriate ioctl for device
+
+.. c:macro:: UV_EFTYPE
+
+    inappropriate file type or format
+
+.. c:macro:: UV_EILSEQ
+
+    illegal byte sequence
+
+.. c:macro:: UV_ESOCKTNOSUPPORT
+
+    socket type not supported
+
+.. c:macro:: UV_EUNATCH
+
+    protocol driver not attached
+
+API
+---
+
+.. c:macro:: UV_ERRNO_MAP(iter_macro)
+
+    Macro that expands to a series of invocations of `iter_macro` for
+    each of the error constants above. `iter_macro` is invoked with two
+    arguments: the name of the error constant without the `UV_` prefix,
+    and the error message string literal.
+
+.. c:function:: const char* uv_strerror(int err)
+
+    Returns the error message for the given error code.  Leaks a few bytes
+    of memory when you call it with an unknown error code.
+
+.. c:function:: char* uv_strerror_r(int err, char* buf, size_t buflen)
+
+    Returns the error message for the given error code. The zero-terminated
+    message is stored in the user-supplied buffer `buf` of at most `buflen` bytes.
+
+    .. versionadded:: 1.22.0
+
+.. c:function:: const char* uv_err_name(int err)
+
+    Returns the error name for the given error code.  Leaks a few bytes
+    of memory when you call it with an unknown error code.
+
+.. c:function:: char* uv_err_name_r(int err, char* buf, size_t buflen)
+
+    Returns the error name for the given error code. The zero-terminated
+    name is stored in the user-supplied buffer `buf` of at most `buflen` bytes.
+
+    .. versionadded:: 1.22.0
+
+.. c:function:: int uv_translate_sys_error(int sys_errno)
+
+   Returns the libuv error code equivalent to the given platform dependent error
+   code: POSIX error codes on Unix (the ones stored in `errno`), and Win32 error
+   codes on Windows (those returned by `GetLastError()` or `WSAGetLastError()`).
+
+   If `sys_errno` is already a libuv error, it is simply returned.
+
+   .. versionchanged:: 1.10.0 function declared public.