Function isatty [src]

Test whether a file descriptor refers to a terminal.

Prototype

pub fn isatty(handle: fd_t) bool

Parameters

handle: fd_t

Source

  pub fn isatty(handle: fd_t) bool {
    if (native_os == .windows) {
        if (fs.File.isCygwinPty(.{ .handle = handle }))
            return true;

        var out: windows.DWORD = undefined;
        return windows.kernel32.GetConsoleMode(handle, &out) != 0;
    }
    if (builtin.link_libc) {
        return system.isatty(handle) != 0;
    }
    if (native_os == .wasi) {
        var statbuf: wasi.fdstat_t = undefined;
        const err = wasi.fd_fdstat_get(handle, &statbuf);
        if (err != .SUCCESS)
            return false;

        // A tty is a character device that we can't seek or tell on.
        if (statbuf.fs_filetype != .CHARACTER_DEVICE)
            return false;
        if (statbuf.fs_rights_base.FD_SEEK or statbuf.fs_rights_base.FD_TELL)
            return false;

        return true;
    }
    if (native_os == .linux) {
        while (true) {
            var wsz: winsize = undefined;
            const fd: usize = @bitCast(@as(isize, handle));
            const rc = linux.syscall3(.ioctl, fd, linux.T.IOCGWINSZ, @intFromPtr(&wsz));
            switch (linux.E.init(rc)) {
                .SUCCESS => return true,
                .INTR => continue,
                else => return false,
            }
        }
    }
    return system.isatty(handle) != 0;
}  