fish-shell/share/functions/isatty.fish
2017-07-12 22:38:32 -07:00

31 lines
712 B
Fish

function isatty -d "Tests if a file descriptor is a tty"
set -l options 'h/help'
argparse -n isatty $options -- $argv
or return
if set -q _flag_help
__fish_print_help isatty
return 0
end
if set -q argv[2]
printf (_ "%s: Too many arguments") isatty >&2
return 1
end
set -l fd
switch "$argv"
case stdin ''
set fd 0
case stdout
set fd 1
case stderr
set fd 2
case '*'
set fd $argv[1]
end
# Use `command test` because `builtin test` doesn't open the regular fd's.
# See https://github.com/fish-shell/fish-shell/issues/1228
command test -t "$fd"
end