dirSymLinkPosix

fn dirSymLinkPosix(
    userdata: ?*anyopaque,
    dir: Dir,
    target_path: []const u8,
    sym_link_path: []const u8,
    flags: Dir.SymLinkFlags,
) Dir.SymLinkError!void {
    _ = flags;
    const t: *Threaded = @ptrCast(@alignCast(userdata));
    _ = t;

    var target_path_buffer: [posix.PATH_MAX]u8 = undefined;
    var sym_link_path_buffer: [posix.PATH_MAX]u8 = undefined;

    const target_path_posix = try pathToPosix(target_path, &target_path_buffer);
    const sym_link_path_posix = try pathToPosix(sym_link_path, &sym_link_path_buffer);

    const syscall: Syscall = try .start();
    while (true) {
        switch (posix.errno(posix.system.symlinkat(target_path_posix, dir.handle, sym_link_path_posix))) {
            .SUCCESS => return syscall.finish(),
            .INTR => {
                try syscall.checkCancel();
                continue;
            },
            else => |e| {
                syscall.finish();
                switch (e) {
                    .FAULT => |err| return errnoBug(err),
                    .INVAL => |err| return errnoBug(err),
                    .ACCES => return error.AccessDenied,
                    .PERM => return error.PermissionDenied,
                    .DQUOT => return error.DiskQuota,
                    .EXIST => return error.PathAlreadyExists,
                    .IO => return error.FileSystem,
                    .LOOP => return error.SymLinkLoop,
                    .NAMETOOLONG => return error.NameTooLong,
                    .NOENT => return error.FileNotFound,
                    .NOTDIR => return error.NotDir,
                    .NOMEM => return error.SystemResources,
                    .NOSPC => return error.NoSpaceLeft,
                    .ROFS => return error.ReadOnlyFileSystem,
                    .ILSEQ => return error.BadPathName,
                    else => |err| return posix.unexpectedErrno(err),
                }
            },
        }
    }
}