Displays process status
The ps utility displays status information about processes.
The process-list is a comma- or SPACE-separated list of PID numbers. When you specify a process-list, ps reports only on processes in that list. The process-list must follow all options on the command line.
The version of ps that Red Hat includes takes three types of options, each preceded by a different prefix. You can intermix the options.
Two hyphens: GNU options
One hyphen: UNIX98 options
No hyphens: BSD options
all Reports on all processes. Also -e.
everything Reports on all processes. Also -A.
full Displays a listing with more columns of information.
Displays the process tree.
long Produces ...