Guide to Unix/Commands/Process Management
nohup lets you run a program in a way which makes it ignore hangup signals. This can be used to make a program continue running after a user has logged out. The output of the program is redirected from the standard output to the file nohup.out.
$ nohup wget http://foo.org/foo_list.gz nohup: appending output to `nohup.out' $
ps displays a list of current processes and their properties.
Processes owned by the current user:
$ ps PID TTY TIME CMD 17525 pts/0 00:00:00 su 17528 pts/0 00:00:00 bash 17590 pts/0 00:00:00 ps where pid is process id.
$ ps -A
kill is used to send termination signals to processes.
To send the kill signal to the processes with process id 17525,
$ kill -9 17525
To send the kill signal to all processes,
$ kill -9 -1
pgrep search and kill system processes
Example: Check if apache webserver is running.
$ pgrep -f apache 5580 5581 5582 5583 5584 5585 or $ svcs -a | grep -i apache.
Stop xterm program with 'pkill' program:
$ pkill -9 xterm
Tips: Display all the process of a user
$ pgrep -l -u arky 894 bash 895 bash 897 bash 898 bash 899 bash 1045 links 1396 startx 1407 xinit 1411 openbox 1412 xterm 1413 xfaces 1414 xsetroot 1415 emacs
pidof display Process ID (PID) of a task
Example: Display the PID of emacs process:
$ pidof emacs 1415
killall kill a process by name
Kill the 'xfaces' program:
$ killall xfacesLast modified on 7 March 2011, at 05:34