Ps (Unix)

In most Unix and Unix-like operating systems, the   (process status) program displays the currently-running processes. The related Unix utility  provides a real-time view of the running processes.

Implementations
KolibriOS includes an implementation of the ps command. The ps command has also been ported to the IBM i operating system. In Windows PowerShell,  is a predefined command alias for the   cmdlet, which essentially serves the same purpose.

Examples
Users can pipeline  with other commands, such as less to view the process status output one page at a time:

Users can also utilize the  command in conjunction with the    command (see the   and   commands) to find information about a single process, such as its id:

The use of  simplifies the syntax and avoids potential race conditions:

To see every process running as root in user format:

Header line
* = Often abbreviated

Options
has many options. On operating systems that support the SUS and POSIX standards,  commonly runs with the options -ef, where "-e" selects every process and "-f" chooses the "full" output format. Another common option on these systems is -l, which specifies the "long" output format.

Most systems derived from BSD fail to accept the SUS and POSIX standard options because of historical conflicts. (For example, the "e" or "-e" option will display environment variables.) On such systems,  commonly runs with the non-standard options aux, where "a" lists all processes on a terminal, including those of other users, "x" lists all processes without controlling terminals and "u" adds a column for the controlling user for each process. For maximum compatibility, there is no "-" in front of the "aux". "ps auxww" provides complete information about the process, including all parameters.