posixStatFile

fn posixStatFile(dir_fd: posix.fd_t, sub_path: [:0]const u8, flags: u32) Dir.StatFileError!File.Stat {
    const syscall: Syscall = try .start();
    while (true) {
        var stat = std.mem.zeroes(posix.Stat);
        switch (posix.errno(fstatat_sym(dir_fd, sub_path, &stat, flags))) {
            .SUCCESS => {
                syscall.finish();
                return statFromPosix(&stat);
            },
            .INTR => {
                try syscall.checkCancel();
                continue;
            },
            else => |e| {
                syscall.finish();
                switch (e) {
                    .INVAL => |err| return errnoBug(err),
                    .BADF => |err| return errnoBug(err), // File descriptor used after closed.
                    .NOMEM => return error.SystemResources,
                    .ACCES => return error.AccessDenied,
                    .PERM => return error.PermissionDenied,
                    .FAULT => |err| return errnoBug(err),
                    .NAMETOOLONG => return error.NameTooLong,
                    .LOOP => return error.SymLinkLoop,
                    .NOENT => return error.FileNotFound,
                    .NOTDIR => return error.FileNotFound,
                    .ILSEQ => return error.BadPathName,
                    else => |err| return posix.unexpectedErrno(err),
                }
            },
        }
    }
}