Is it a terminal?

isatty(){ test -t $1; }
Oddly, the isatty(3) glibc C call doesn't have a direct analogue as a command 'isatty(1)'. All is not lost as you can use test(1). For example, your script might be run from a tty or from a GUI menu item but it needs to get user-input or give feedback. Now your script can test STDIN with 'isatty 0' or STDOUT with 'isatty 1' and use xmessage(1) if the tty is not available. The other way to test for this is with 'tty -s' - but that's only for STDIN.

3
By: bhepple
2010-01-06 06:50:01

2 Alternatives + Submit Alt

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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