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Make sure a script is run in a terminal.

Terminal - Make sure a script is run in a terminal.
tty > /dev/null 2>&1 || { aplay error.wav ; exit 1 ;}
2009-11-04 16:18:00
User: johnraff
Functions: aplay exit tty
0
Make sure a script is run in a terminal.

If your script needs to be run in a terminal, this line at the top will stop it running if you absent-mindedly double-click the icon, perhaps intending to edit it. (Of course this won't help with scripts that run in the background.)

Alternatives

There are 7 alternatives - vote for the best!

Terminal - Alternatives
[ -t 0 ] || exit 1
2009-11-20 23:14:49
User: cfajohnson
Functions: exit
Tags: shell script
21

Exit with error if script is not run in a terminal

isatty(){ test -t $1; }
2010-01-06 06:50:01
User: bhepple
Functions: test
3

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.

Know a better way?

If you can do better, submit your command here.

What others think

I believe you meant "exit 1" instead of "exit 0". Zero signals that there was no error.

Comment by hackerb9 367 weeks and 4 days ago

Well, that's up to you I suppose. I meant "no error" in the sense that the problem was with how the script was started, not with the script itself. Set it to "1" if you prefer.

Comment by johnraff 367 weeks and 2 days ago

On reflection you're right, hackerb9. Even if the script is blameless, if the user doesn't get the result (s)he wanted then there was an error. I'll edit the line.

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Comment by jiajiagg 14 weeks ago

Your point of view

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