1. We have moved from vBulletin to XenForo and you are viewing the site in the middle of the move. Though the functional aspect of everything is working fine, we are still working on other changes including the new design on Xenforo.
    Dismiss Notice

Kill All Processes Matching A Pattern In A Single Command

Discussion in 'Unix' started by pradeep, May 30, 2009.

  1. pradeep

    pradeep Team Leader

    Introduction


    Many times we write programs which runs many instances of itself, either while using fork or we manually run many copies of the same program, so during the development stage we may need to kill all running instances and modify the program and re-run, or there may be other situations where we may need to kill a ll perl programs running, etc etc. Till a few months back I used to do this job of killing manually process id by process id, like this

    Code:
    [root@pradeep test]# kill 31372
    But recently I devised a command to kill all processes matching a pattern, I am sure someone else must have already done this, but there must any other to whom this might be helpful.

    The Command



    The command looks like this

    Code:
    ps ax|grep pl|awk '{print $1}'|xargs kill
    Well, to some it might look confusing, let me break up the command a explain.

    ps ax|grep pl
    Returns all commands running which have 'pl' in them, so 'pl' is my pattern, you may write any pattern you want, here's the output of the command how it looks on my system.

    Code:
    [root@pradeep test]# ps ax|grep pl
    31372 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31375 ?        S      0:00 ./test.pl
    31455 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31456 ?        S      0:00 ./test.pl
    31460 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31463 ?        S      0:00 ./test.pl
    31493 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31494 ?        S      0:00 ./test.pl
    31495 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31496 ?        S      0:00 ./test.pl
    31528 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31529 ?        S      0:00 ./test.pl
    31532 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31533 ?        S      0:00 ./test.pl
    31565 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31566 ?        S      0:00 ./test.pl
    31569 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31570 ?        S      0:00 ./test.pl
    31603 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31604 ?        S      0:00 ./test.pl
    31607 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31608 ?        S      0:00 ./test.pl
    31635 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31636 ?        S      0:00 ./test.pl
    31639 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31640 ?        S      0:00 ./test.pl
    31670 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31671 ?        S      0:00 ./test.pl
    31672 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31673 ?        S      0:00 ./test.pl
    31674 ?        Ss     0:00 /bin/sh -c cd /home/pradeep/test ; ./test.pl
    31675 ?        S      0:00 ./test.pl
    31681 ?        S      0:00 ./test.pl
    31686 ?        S      0:00 ./test.pl
    31693 ?        S      0:00 ./test.pl
    31699 pts/0    R+     0:00 grep pl
    
    awk '{print $1}'
    Prints the first column returned by the previous command, in this case the PID e.g. - 31671

    xargs kill
    Use xargs to pass the PID printed by the previous command to kill command

    I hope this is helpful.
     
  2. shabbir

    shabbir Administrator Staff Member

  3. janu03

    janu03 Banned

    If the command name is not regular expression (option -r) and contains a slash ... context that match with given expended regular expression pattern. ... If processes change their name, killall may not be able to match them correctly. ..
     

Share This Page