NAME

ps — process status

SYNOPSIS

ps	[-AaCcehjlmrSsTuvwx] [-k key] [-M core] [-N system] [-O fmt] [-o fmt] [-p pid] [-t tty] [-U user] [-W swap]

ps

-L

DESCRIPTION

ps displays a header line followed by lines containing information about running processes. By default, the display includes only processes that have controlling terminals and are owned by your uid. The default sort order of controlling terminal and (among processes with the same controlling terminal) process ID may be changed using the -k, -m, or -r options.

The information displayed for each process is selected based on a set of keywords (see the -L, -O, and -o options). The default output format includes, for each process, the process' ID, controlling terminal, CPU time (including both user and system time), state, and associated command.

The options are as follows:

-A

Display information about all processes. This is equivalent to -a -x.

-a

Display information about other users' processes as well as your own. Note that this does not display information about processes without controlling terminals.

-C

Change the way the CPU percentage is calculated by using a “raw” CPU calculation that ignores “resident” time (this normally has no effect).

-c

Do not display full command with arguments, but only the executable name. This may be somewhat confusing; for example, all sh(1) scripts will show as “sh”.

-e

Display the environment as well. The environment for other users' processes can only be displayed by the super-user.

-h

Repeat the information header as often as necessary to guarantee one header per page of information.

-j

Print information associated with the following keywords: user, pid, ppid, pgid, sess, jobc, state, tt, time, and command.

-k key

Sort the output using the space or comma separated list of keywords. Multiple sort keys may be specified, using any of the -k, -m, or -r options. The default sort order is equivalent to -k tdev,pid.

-L

List the set of available keywords.

-l

Display information associated with the following keywords: uid, pid, ppid, cpu, pri, nice, vsz, rss, wchan, state, tt, time, and command.

-M core

Extract values from the specified core file instead of the running system.

-m

Sort by memory usage. This is equivalent to -k vsz.

-N system

Extract the name list from the specified system instead of the default, “/netbsd”. Ignored unless -M is specified.

-O fmt

Display information associated with the space or comma separated list of keywords specified. The -O option does not suppress the default display; it inserts additional keywords just after the pid keyword in the default display, or after the pid keyword (if any) in a non-default display specified before the first use of the -O flag. Keywords inserted by multiple -O options will be adjacent.

An equals sign (“=”) followed by a customised header string may be appended to a keyword, as described in more detail under the -o option.

-o fmt

Display information associated with the space or comma separated list of keywords specified. Use of the -o option suppresses the set of keywords that would be displayed by default, or appends to the set of keywords specified by other options.

An equals sign (“=”) followed by a customised header string may be appended to a keyword. This causes the printed header to use the specified string instead of the default header associated with the keyword.

Everything after the first equals sign is part of the customised header text, and this may include embedded spaces (“ ”), commas (“,”), or equals signs (“=”). To specify multiple keywords with customised headers, use multiple -o or -O options.

If all the keywords to be displayed have customised headers, and all the customised headers are entirely empty, then the header line is not printed at all.

-p pid

Display information associated with the specified process ID.

-r

Sort by current CPU usage. This is equivalent to -k %cpu.

-S

Change the way the process time is calculated by summing all exited children to their parent process.

-s

Display one line for each LWP, rather than one line for each process, and display information associated with the following keywords: uid, pid, ppid, cpu, lid, nlwp, pri, nice, vsz, rss, wchan, lstate, tt, time, and command.

-T

Display information about processes attached to the device associated with the standard input.

-t tty

Display information about processes attached to the specified terminal device. Use a question mark (“?”) for processes not attached to a terminal device and a minus sign (“-”) for processes that have been revoked from their terminal device.

-U user

Display processes belonging to the specified user, given either as a user name or a uid.

-u

Display information associated with the following keywords: user, pid, %cpu, %mem, vsz, rss, tt, state, start, time, and command. The -u option implies the -r option.

-v

Display information associated with the following keywords: pid, state, time, sl, re, pagein, vsz, rss, lim, tsiz, %cpu, %mem, and command. The -v option implies the -m option.

-W swap

Extract swap information from the specified file instead of the default, “/dev/drum”. Ignored unless -M is specified.

-w

Use 132 columns to display information instead of the default, which is your window size. If the -w option is specified more than once, ps will use as many columns as necessary without regard to your window size.

-x

Also display information about processes without controlling terminals.

A complete list of the available keywords are listed below. Some of these keywords are further specified as follows:

%cpu

The CPU utilization of the process; this is a decaying average over up to a minute of previous (real) time. Since the time base over which this is computed varies (since processes may be very young) it is possible for the sum of all %CPU fields to exceed 100%.

%mem

The percentage of real memory used by this process.

flags

The flags (in hexadecimal) associated with the process as in the include file <sys/proc.h>:

P_ADVLOCK	0x00000001	process may hold a POSIX advisory lock
P_CONTROLT	0x00000002	process has a controlling terminal
P_NOCLDSTOP	0x00000008	no SIGCHLD when children stop
P_PPWAIT	0x00000010	parent is waiting for child to exec/exit
P_PROFIL	0x00000020	process has started profiling
P_SELECT	0x00000040	selecting; wakeup/waiting danger
P_SINTR	0x00000080	sleep is interruptible
P_SUGID	0x00000100	process had set id privileges since last exec
P_SYSTEM	0x00000200	system process: no sigs or stats
P_TIMEOUT	0x00000400	timing out during sleep
P_TRACED	0x00000800	process is being traced
P_WAITED	0x00001000	debugging process has waited for child
P_WEXIT	0x00002000	working on exiting
P_EXEC	0x00004000	process called execve(2)
P_OWEUPC	0x00008000	owe process an addupc() call at next ast
P_FSTRACE	0x00010000	tracing via file system
P_NOCLDWAIT	0x00020000	no zombies when children die
P_32	0x00040000	32-bit process (used on 64-bit kernels)
P_BIGLOCK	0x00080000	process needs kernel ``big lock'' to run
P_INEXEC	0x00100000	process is exec'ing and cannot be traced

lim

The soft limit on memory used, specified via a call to setrlimit(2).

lstart

The exact time the command started, using the “%c” format described in strftime(3).

nice

The process scheduling increment (see setpriority(2)).

rss

the real memory (resident set) size of the process (in 1024 byte units).

start

The time the command started. If the command started less than 24 hours ago, the start time is displayed using the “%l:%M%p” format described in strftime(3). If the command started less than 7 days ago, the start time is displayed using the “%a%p” format. Otherwise, the start time is displayed using the “%e%b%y” format.

state

The state is given by a sequence of letters, for example, “RNs”. The first letter indicates the run state of the process:

D

Marks a process in device or other short term, uninterruptible wait.

I

Marks a process that is idle (sleeping interruptibly for longer than about MAXSLP (default 20) seconds).

O

Marks a process running on a processor.

R

Marks a runnable process, or one that is in the process of creation.

S

Marks a process that is sleeping interruptibly for less than about MAXSLP (default 20) seconds.

T

Marks a stopped process.

U

Marks a suspended process.

Z

Marks a dead process that has exited, but not been waited for (a “zombie”).

Additional characters after these, if any, indicate additional state information:

+

The process is in the foreground process group of its control terminal.

-

The LWP is detached (can't be waited for).

<

The process has raised CPU scheduling priority.

a

The process is using scheduler activations (deprecated).

E

The process is in the process of exiting.

K

The process is a kernel thread or system process.

l

The process has multiple LWPs.

N

The process is niced (has reduced CPU scheduling priority) (see setpriority(2)).

s

The process is a session leader.

V

The process is suspended during a vfork(2).

X

The process is being traced or debugged.

tt

An abbreviation for the pathname of the controlling terminal, if any. The abbreviation consists of the two letters following “/dev/tty” or, for the console, “co”. This is followed by a “-” if the process can no longer reach that controlling terminal (i.e., it has been revoked).

wchan

The event (an address in the system) on which a process waits. When printed numerically, the initial part of the address is trimmed off and the result is printed in hex, for example, 0x80324000 prints as 324000.

When printing using the command keyword, a process that has exited and has a parent that has not yet waited for the process (in other words, a zombie) is listed as “<defunct>”, and a process which is blocked while trying to exit is listed as “<exiting>”.

ps will try to locate the processes' argument vector from the user area in order to print the command name and arguments. This method is not reliable because a process is allowed to destroy this information. The ucomm (accounting) keyword will always contain the real command name as contained in the process structure's p_comm field.

If the command vector cannot be located (usually because it has not been set, as is the case of system processes and/or kernel threads) the command name is printed within square brackets.

To indicate that the argument vector has been tampered with, ps will append the real command name to the output within parentheses if the basename of the first argument in the argument vector does not match the contents of the real command name.

In addition, ps checks for the following two situations and does not append the real command name parenthesized:

-shellname

The login process traditionally adds a ‘-’ in front of the shell name to indicate a login shell. ps will not append parenthesized the command name if it matches with the name in the first argument of the argument vector, skipping the leading ‘-’.

daemonname: current-activity

Daemon processes frequently report their current activity by setting their name to be like “daemonname: current-activity”. ps will not append parenthesized the command name, if the string preceding the ‘:’ in the first argument of the argument vector matches the command name.

KEYWORDS

The following is a complete list of the available keywords and their meanings. Several of them have aliases (keywords which are synonyms).

%cpu

percentage CPU usage (alias pcpu)

%mem

percentage memory usage (alias pmem)

acflag

accounting flag (alias acflg)

comm

command (the argv[0] value)

command

command and arguments (alias args)

cpu

short-term CPU usage factor (for scheduling)

cpuid

CPU number the current process or lwp is running on.

ctime

accumulated CPU time of all children that have exited

egid

effective group id

egroup

group name (from egid)

emul

emulation name

etime

elapsed time since the process was started, in the form [[dd-]hh:]mm:ss

euid

effective user id

euser

user name (from euid)

flags

the process flags, in hexadecimal (alias f)

gid

effective group id

group

group name (from gid)

groupnames

group names (from group access list)

groups

group access list

inblk

total blocks read (alias inblock)

jobc

job control count

ktrace

tracing flags

ktracep

tracing vnode

laddr

kernel virtual address of the struct lwp belonging to the LWP.

lid

ID of the LWP

lim

memory use limit

lname

descriptive name of the LWP

logname

login name of user who started the process (alias login)

lstart

time started

lstate

symbolic LWP state

ltime

CPU time of the LWP

majflt

total page faults

minflt

total page reclaims

msgrcv

total messages received (reads from pipes/sockets)

msgsnd

total messages sent (writes on pipes/sockets)

nice

nice value (alias ni)

nivcsw

total involuntary context switches

nlwp

number of LWPs in the process

nsigs

total signals taken (alias nsignals)

nvcsw

total voluntary context switches

nwchan

wait channel (as an address)

oublk

total blocks written (alias oublock)

p_ru

resource usage pointer (valid only for zombie)

paddr

kernel virtual address of the struct proc belonging to the process.

pagein

pageins (same as majflt)

pgid

process group number

pid

process ID

ppid

parent process ID

pri

scheduling priority

re

core residency time (in seconds; 127 = infinity)

rgid

real group ID

rlink

reverse link on run queue, or 0

rlwp

number of LWPs on a processor or run queue

rss

resident set size

rsz

resident set size + (text size / text use count) (alias rssize)

ruid

real user ID

ruser

user name (from ruid)

sess

session pointer

sid

session ID

sig

pending signals (alias pending)

sigcatch

caught signals (alias caught)

sigignore

ignored signals (alias ignored)

sigmask

blocked signals (alias blocked)

sl

sleep time (in seconds; 127 = infinity)

start

time started

state

symbolic process state (alias stat)

stime

accumulated system CPU time

svgid

saved gid from a setgid executable

svgroup

group name (from svgid)

svuid

saved uid from a setuid executable

svuser

user name (from svuid)

tdev

control terminal device number

time

accumulated CPU time, user + system (alias cputime)

tpgid

control terminal process group ID

tsess

control terminal session pointer

tsiz

text size (in Kbytes)

tt

control terminal name (two letter abbreviation)

tty

full name of control terminal

uaddr

kernel virtual address of the struct user belonging to the LWP.

ucomm

name to be used for accounting

uid

effective user ID

upr

scheduling priority on return from system call (alias usrpri)

user

user name (from uid)

utime

accumulated user CPU time

vsz

virtual size in Kbytes (alias vsize)

wchan

wait channel (as a symbolic name)

xstat

exit or stop status (valid only for stopped or zombie process)

FILES

/dev

special files and device names

/dev/drum

default swap device

/var/run/dev.cdb

/dev name database

/var/db/kvm.db

system name list database

/netbsd

default system name list

SEE ALSO

kill(1), pgrep(1), pkill(1), sh(1), w(1), kvm(3), strftime(3), dev_mkdb(8), pstat(8)

BUGS

Since ps cannot run faster than the system and is run as any other scheduled process, the information it displays can never be exact.