Commands using tty (3)


  • 0
    TTY=$(tty | cut -c 6-);who | grep "$TTY " | awk '{print $6}' | tr -d '()'
    sharfah · 2010-08-06 13:42:17 3
  • 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.)


    0
    tty > /dev/null 2>&1 || { aplay error.wav ; exit 1 ;}
    johnraff · 2009-11-04 16:18:00 3
  • A common mistake in Bash is to write command-line where there's command a reading a file and whose result is redirected to that file. It can be easily avoided because of : 1) warnings "-bash: file.txt: cannot overwrite existing file" 2) options (often "-i") that let the command directly modify the file but I like to have that small function that does the trick by waiting for the first command to end before trying to write into the file. Lots of things could probably done in a better way, if you know one... Show Sample Output


    2
    buffer () { tty -s && return; tmp=$(mktemp); cat > "${tmp}"; if [ -n "$1" ] && ( ( [ -f "$1" ] && [ -w "$1" ] ) || ( ! [ -a "$1" ] && [ -w "$(dirname "$1")" ] ) ); then mv -f "${tmp}" "$1"; else echo "Can't write in \"$1\""; rm -f "${tmp}"; fi }
    Josay · 2009-07-27 20:21:15 3

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