ps [options]

Report on active processes. ps has three types of options. GNU long options start with two dashes, which are required. BSD options may be grouped and do not start with a dash, while Unix98 options may be grouped and require an initial dash. The meaning of the short options can vary depending on whether or not there is a dash. In options, list arguments should either be separated by commas or put in double quotes. In comparing the amount of output produced, note that e prints more than a and l prints more than f for each entry.


nums, pnums, -pnums, --pid=nums

Include only specified processes, which are given in a space-delimited list.

--nums, --sid=nums

Include only specified session IDs, which are given in a space-delimited list.


As a, list all processes on a terminal. As -a, list all processes on a terminal except session leaders.


As c, show the true command name. As -c, show different scheduler information with -l.

-C cmds

Select by command name.

--cols=cols, --columns=cols, --width=cols

Set the output width (the number of columns to display).


Select all processes except session leaders.

-e, -A

Select all processes.


Include environment information after the command.

[-]f, -F, --forest

As -f, display full listing. As f or --forest, display “forest” family tree format, with ASCII art showing the relationships.

-glist, -Glist, --group=groups, --Group=groups

For -g, select by session leader if list contains numbers, or by group if it contains group ...

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