Function readlinkat [src]

Similar to readlink except reads value of a symbolink link relative to dirfd directory handle. On Windows, file_path should be encoded as WTF-8. On WASI, file_path should be encoded as valid UTF-8. On other platforms, file_path is an opaque sequence of bytes with no particular encoding. The return value is a slice of out_buffer from index 0. On Windows, the result is encoded as WTF-8. On WASI, the result is encoded as UTF-8. On other platforms, the result is an opaque sequence of bytes with no particular encoding. See also readlinkatWasi, realinkatZ and realinkatW.

Prototype

pub fn readlinkat(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8

Parameters

dirfd: fd_tfile_path: []const u8out_buffer: []u8

Possible Errors

AccessDenied

In WASI, this error may occur when the file descriptor does not hold the required rights to read value of a symbolic link relative to it.

BadPathName

FileNotFound

FileSystem

InvalidUtf8

WASI-only; file paths must be valid UTF-8.

InvalidWtf8

Windows-only; file paths provided by the user must be valid WTF-8. https://simonsapin.github.io/wtf-8/

NameTooLong

NetworkNotFound

On Windows, \\server or \\server\share was not found.

NotDir

NotLink

PermissionDenied

SymLinkLoop

SystemResources

Unexpected UnexpectedError

The Operating System returned an undocumented error code.

This error is in theory not possible, but it would be better to handle this error than to invoke undefined behavior.

When this error code is observed, it usually means the Zig Standard Library needs a small patch to add the error code to the error set for the respective function.

UnsupportedReparsePointType

Windows-only. This error may occur if the opened reparse point is of unsupported type.

Source

  pub fn readlinkat(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 {
    if (native_os == .wasi and !builtin.link_libc) {
        return readlinkatWasi(dirfd, file_path, out_buffer);
    }
    if (native_os == .windows) {
        const file_path_w = try windows.sliceToPrefixedFileW(dirfd, file_path);
        return readlinkatW(dirfd, file_path_w.span(), out_buffer);
    }
    const file_path_c = try toPosixPath(file_path);
    return readlinkatZ(dirfd, &file_path_c, out_buffer);
}  