Function openDir [src]

Opens a directory at the given path. The directory is a system resource that remains open until close is called on the result. The directory cannot be iterated unless the iterate option is set to true. On Windows, sub_path should be encoded as WTF-8. On WASI, sub_path should be encoded as valid UTF-8. On other platforms, sub_path is an opaque sequence of bytes with no particular encoding. Asserts that the path parameter has no null bytes.

Prototype

pub fn openDir(self: Dir, sub_path: []const u8, args: OpenOptions) OpenError!Dir

Parameters

self: Dirsub_path: []const u8args: OpenOptions

Possible Errors

AccessDenied

BadPathName

DeviceBusy

FileNotFound

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.

NoDevice

NotDir

PermissionDenied

ProcessFdQuotaExceeded

SymLinkLoop

SystemFdQuotaExceeded

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.

Source

  pub fn openDir(self: Dir, sub_path: []const u8, args: OpenOptions) OpenError!Dir {
    switch (native_os) {
        .windows => {
            const sub_path_w = try windows.sliceToPrefixedFileW(self.fd, sub_path);
            return self.openDirW(sub_path_w.span().ptr, args);
        },
        .wasi => if (!builtin.link_libc) {
            var base: std.os.wasi.rights_t = .{
                .FD_FILESTAT_GET = true,
                .FD_FDSTAT_SET_FLAGS = true,
                .FD_FILESTAT_SET_TIMES = true,
            };
            if (args.access_sub_paths) {
                base.FD_READDIR = true;
                base.PATH_CREATE_DIRECTORY = true;
                base.PATH_CREATE_FILE = true;
                base.PATH_LINK_SOURCE = true;
                base.PATH_LINK_TARGET = true;
                base.PATH_OPEN = true;
                base.PATH_READLINK = true;
                base.PATH_RENAME_SOURCE = true;
                base.PATH_RENAME_TARGET = true;
                base.PATH_FILESTAT_GET = true;
                base.PATH_FILESTAT_SET_SIZE = true;
                base.PATH_FILESTAT_SET_TIMES = true;
                base.PATH_SYMLINK = true;
                base.PATH_REMOVE_DIRECTORY = true;
                base.PATH_UNLINK_FILE = true;
            }

            const result = posix.openatWasi(
                self.fd,
                sub_path,
                .{ .SYMLINK_FOLLOW = !args.no_follow },
                .{ .DIRECTORY = true },
                .{},
                base,
                base,
            );
            const fd = result catch |err| switch (err) {
                error.FileTooBig => unreachable, // can't happen for directories
                error.IsDir => unreachable, // we're setting DIRECTORY
                error.NoSpaceLeft => unreachable, // not setting CREAT
                error.PathAlreadyExists => unreachable, // not setting CREAT
                error.FileLocksNotSupported => unreachable, // locking folders is not supported
                error.WouldBlock => unreachable, // can't happen for directories
                error.FileBusy => unreachable, // can't happen for directories
                else => |e| return e,
            };
            return .{ .fd = fd };
        },
        else => {},
    }
    const sub_path_c = try posix.toPosixPath(sub_path);
    return self.openDirZ(&sub_path_c, args);
}  