PS(1) OpenBSD Reference Manual PS(1)
ps - process status
ps [-acCehjlmrSTuvwx] [-M core] [-N system] [-O fmt] [-o fmt] [-p pid]
[-t tty] [-U username] [-W swap]
The ps utility displays information about active processes. When given
no options, ps prints information about processes associated with the
The information displayed is selected based on a set of keywords (and for
even more control, see the -L, -O, and -o options). The default output
format includes, for each process, the process's ID, controlling termi-
nal, CPU time (including both user and system time), state, and associat-
The options are as follows:
-a Display information about other users' processes as well as your
-c Do not display full command with arguments, but only the exe-
cutable name. This may be somewhat confusing; for example, all
sh(1) scripts will show as ``sh''.
-C Change the way the CPU percentage is calculated by using a
``raw'' CPU calculation that ignores ``resident'' time (this nor-
mally has no effect).
-e Display the environment as well.
-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.
-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
Extract values associated with the name list from the specified
core instead of the default ``/dev/kmem''.
-m Sort by memory usage, instead of by process ID.
Extract the name list from the specified system instead of the
-O fmt Add the information associated with the space or comma separated
list of keywords specified, after the process ID, in the default
information display. Keywords may be appended with an equals
sign (`=') and a string. This causes the printed header to use
the specified string instead of the standard header.
-o fmt Display information associated with the space or comma separated
list of keywords specified. Keywords may be appended with an
equals sign (`=') and a string. This causes the printed header
to use the specified string instead of the standard header.
-p pid Display information associated with the specified process ID.
-r Sort by current CPU usage, instead of by process ID.
-S Change the way the process time is calculated by summing all ex-
ited children to their parent process.
-T Display information about processes attached to the device asso-
ciated with the standard input.
-t tty Display information about processes attached to the specified
Display the processes belonging to the specified username.
-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.
Extract swap information from the specified file instead of the
-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 re-
gard for your window size.
-x Display information about processes without controlling termi-
All available keywords are listed below. Some of these keywords are fur-
ther 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
%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 0x0000001 process may hold a POSIX advisory
P_CONTROLT 0x0000002 process has a controlling terminal
P_INMEM 0x0000004 process is loaded into memory
P_NOCLDSTOP 0x0000008 no SIGCHLD when children stop
P_PPWAIT 0x0000010 parent is waiting for child to
P_PROFIL 0x0000020 process has started profiling
P_SELECT 0x0000040 selecting; wakeup/waiting danger
P_SINTR 0x0000080 sleep is interruptible
P_SUGID 0x0000100 process had set id privileges since
P_SYSTEM 0x0000200 system process: no sigs, stats or
P_TIMEOUT 0x0000400 timing out during sleep
P_TRACED 0x0000800 process is being traced
P_WAITED 0x0001000 debugging process has waited for
P_WEXIT 0x0002000 working on exiting
P_EXEC 0x0004000 process called exec(3)
P_OWEUPC 0x0008000 owe process an addupc() call at
P_FSTRACE 0x0010000 tracing via file system
P_SSTEP 0x0020000 process needs single-step fixup
lim The soft limit on memory used, specified via a call to
lstart The exact time the command started, using the ``%c'' format de-
scribed in strftime(3).
nice The process scheduling increment (see setpriority(2)).
rss The real memory (resident set) size of the process (in 1024 byte
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%I%p''
format. Otherwise, the start time is displayed using the
state The state is given by a sequence of letters, for example,
``RWNA''. The first letter indicates the run state of the pro-
D Marks a process in disk (or other short term, uninter-
I Marks a process that is idle (sleeping for longer than
about 20 seconds).
R Marks a runnable process.
S Marks a process that is sleeping for less than about 20
T Marks a stopped process.
Z Marks a dead process (a ``zombie'').
Additional characters after these, if any, indicate additional
+ The process is in the foreground process group of its
< The process has raised CPU scheduling priority.
> The process has specified a soft limit on memory require-
ments and is currently exceeding that limit; such a pro-
cess is (necessarily) not swapped.
E The process is trying to exit.
L The process has pages locked in core (for example, for
N The process has reduced CPU scheduling priority (see
s The process is a session leader.
V The process is suspended during a vfork(2).
W The process is swapped out.
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 termi-
nal (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 makes an educated guess as
to the file name and arguments given when the process was created by ex-
amining memory or the swap area. The method is inherently somewhat unre-
liable and in any event a process is entitled to destroy this informa-
tion, so the names cannot be depended on too much. The ucomm (account-
ing) keyword can, however, be depended on.
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)
command command and arguments (alias args)
cpu short-term CPU usage factor (for scheduling)
emul name of system call emulation environment
flags the process flags, in hexadecimal (alias f)
gid effective group
group text name of effective group ID
holdcnt number of holds on the process (if non-zero, process can't be
inblk total blocks read (alias inblock)
jobc job control count
ktrace tracing flags
ktracep tracing vnode
lim memoryuse limit
logname login name of user who started the process (alias login)
lstart time started
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
nsigs total signals taken (alias nsignals)
nswap total swaps in/out
nvcsw total voluntary context switches
nwchan wait channel (as an address)
oublk total blocks written (alias oublock)
p_ru resource usage (valid only for zombie)
paddr swap address
pagein pageins (same as majflt)
pgid process group number
pid process ID
poip pageouts in progress
ppid parent process ID
pri scheduling priority
re core residency time (in seconds; 127 = infinity)
rgid real group ID
rgroup text name of real group ID
rlink reverse link on run queue, or 0
rss resident set size
rsz resident set size + (text size / text use count) (alias rs-
ruid real user ID
ruser user name (from ruid)
sess session pointer
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 (alias etime)
state symbolic process state (alias stat)
svgid saved GID from a setgid executable
svuid saved UID from a setuid executable
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
ucomm name to be used for accounting (alias comm)
uid effective user ID
upr scheduling priority on return from system call (alias usrpri)
uprocp process pointer
user user name (from uid)
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)
/dev special files and device names
/dev/drum default swap device
/dev/kmem default kernel memory
/var/run/dev.db /dev name database
/var/db/kvm_bsd.db system namelist database
/bsd default system namelist
kill(1), sh(1), top(1), w(1), kvm(3), strftime(3), pstat(8)
Since ps cannot run faster than the system and is run as any other sched-
uled process, the information it displays can never be exact.
OpenBSD 2.6 April 18, 1994 5
Source: OpenBSD 2.6 man pages. Copyright: Portions are copyrighted by BERKELEY
SOFTWARE DESIGN, INC., The Regents of the University of California, Massachusetts
Institute of Technology, Free Software Foundation, FreeBSD Inc., and others.