The ps utility shall conform to the Base Definitions volume of
POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines.
The following options shall be supported:
-a Write information for all processes associated with
terminals. Implementations may omit session leaders
from this list.
-A Write information for all processes.
-d Write information for all processes, except session
leaders.
-e Write information for all processes. (Equivalent to
-A.)
-f Generate a full listing. (See the STDOUT section for
the contents of a full listing.)
-g grouplist
Write information for processes whose session leaders
are given in grouplist. The application shall ensure
that the grouplist is a single argument in the form of
a <blank> or <comma>-separated list.
-G grouplist
Write information for processes whose real group ID
numbers are given in grouplist. The application shall
ensure that the grouplist is a single argument in the
form of a <blank> or <comma>-separated list.
-l Generate a long listing. (See STDOUT for the contents
of a long listing.)
-n namelist
Specify the name of an alternative system namelist file
in place of the default. The name of the default file
and the format of a namelist file are unspecified.
-o format Write information according to the format specification
given in format. This is fully described in the STDOUT
section. Multiple -o options can be specified; the
format specification shall be interpreted as the
<space>-separated concatenation of all the format
option-arguments.
-p proclist
Write information for processes whose process ID
numbers are given in proclist. The application shall
ensure that the proclist is a single argument in the
form of a <blank> or <comma>-separated list.
-t termlist
Write information for processes associated with
terminals given in termlist. The application shall
ensure that the termlist is a single argument in the
form of a <blank> or <comma>-separated list. Terminal
identifiers shall be given in an implementation-defined
format. On XSI-conformant systems, they shall be given
in one of two forms: the device's filename (for
example, tty04) or, if the device's filename starts
with tty, just the identifier following the characters
tty (for example, "04").
-u userlist
Write information for processes whose user ID numbers
or login names are given in userlist. The application
shall ensure that the userlist is a single argument in
the form of a <blank> or <comma>-separated list. In the
listing, the numerical user ID shall be written unless
the -f option is used, in which case the login name
shall be written.
-U userlist
Write information for processes whose real user ID
numbers or login names are given in userlist. The
application shall ensure that the userlist is a single
argument in the form of a <blank> or <comma>-separated
list.
With the exception of -f, -l, -n namelist, and -o format, all of
the options shown are used to select processes. If any are
specified, the default list shall be ignored and ps shall select
the processes represented by the inclusive OR of all the
selection-criteria options.
