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

-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, --forest

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

-g list, -G list, --group= groups, --Group= groups

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

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