PS

Section: User Commands (1)
Updated: PDP11
Index Return to Main Contents
 

NAME

ps - process status  

SYNOPSIS

ps [ aklx ] [ namelist ]  

DESCRIPTION

Ps prints certain indicia about active processes. The a option asks for information about all processes with terminals (ordinarily only one's own processes are displayed); x asks even about processes with no terminal; l asks for a long listing. The short listing contains the process ID, tty letter, the cumulative execution time of the process and an approximation to the command line.

The long listing is columnar and contains

F
Flags associated with the process. 01: in core; 02: system process; 04: locked in core (e.g. for physical I/O); 10: being swapped; 20: being traced by another process.
S
The state of the process. 0: nonexistent; S: sleeping; W: waiting; R: running; I: intermediate; Z: terminated; T: stopped.
UID
The user ID of the process owner.
PID
The process ID of the process; as in certain cults it is possible to kill a process if you know its true name.
PPID
The process ID of the parent process.
CPU
Processor utilization for scheduling.
PRI
The priority of the process; high numbers mean low priority.
NICE
Used in priority computation.
ADDR
The core address of the process if resident, otherwise the disk address.
SZ
The size in blocks of the core image of the process.
WCHAN
The event for which the process is waiting or sleeping; if blank, the process is running.
TTY
The controlling tty for the process.
TIME
The cumulative execution time for the process.
The command and its arguments.

A process that has exited and has a parent, but has not yet been waited for by the parent is marked <defunct>. Ps makes an educated guess as to the file name and arguments given when the process was created by examining core memory or the swap area. The method is inherently somewhat unreliable and in any event a process is entitled to destroy this information, so the names cannot be counted on too much.

If the k option is specified, the file /usr/sys/core is used in place of /dev/mem. This is used for postmortem system debugging. If a second argument is given, it is taken to be the file containing the system's namelist.  

FILES

/unix         system namelist

/dev/mem     core memory

/usr/sys/corealternate core file

/dev         searched to find swap device and tty names
 

SEE ALSO

kill(1)  

BUGS

Things can change while ps is running; the picture it gives is only a close approximation to reality.
Some data printed for defunct processes is irrelevant


 

Index

NAME
SYNOPSIS
DESCRIPTION
FILES
SEE ALSO
BUGS

This document was created by man2html, using the manual pages.
Time: 10:16:35 GMT, December 28, 2024