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Feldpausch All4
Asked: 2014-05-06 14:53:25 +0800 CST

Do something if a program is running

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Is there something you can type into terminal so that it will run a command if a certain program is running? For example, if <Libre office is running> then sudo pkill <Libre ofice>.

Edit 1: So what I want to do is make an if statement in terminal that runs if a program is running and if it is not it does nothing, or does something else.

command-line

1 Answers

  1. Best Answer

    "what I want to do is make an if statement in terminal that runs if a program is running and if it is not it does nothing, or does something else"

    To determine if a program is running given its name, use pgrep. To dosomething if LibreOffice's word processor is running:

    pgrep soffice.bin >/dev/null && do_something

    Similarly, to do something if LibreOffice's word processor is not running:

    pgrep soffice.bin >/dev/null || do_something

    Further, you can use these two in combination:

    pgrep soffice.bin && do_one_thing || do_another

    Or, if things get more complicated, use an if statement:

    if pgrep soffice.bin
then
    # command is running
    do_one_thing
    do_one_thing2
else
    # command is not running
    do_another
    do_another2
fi

    The above work because pgrep, just like grep, sets a useful exit code. If a process is found, it returns with an exit code of zero (which the shell interprets as logical true). If not, it returns with one (the shell interprets any non-zero exit code to mean false).

    To find out all the programs that are currently running (and hence what name to use as the argument to pgrep), run ps ax

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