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PS(1) Linux User's Manual PS(1)
NAME
ps - report a snapshot of the current processes.
SYNOPSIS
ps [options]
DESCRIPTION
ps displays information about a selection of the active processes. If you
want a repetitive update of the selection and the displayed information,
use top(1) instead.
By default, ps selects all processes with the same effective user ID (EUID)
as the curent user and associated with the same terminal as the invoker. It
displays the process ID (PID), the terminal (tty) associated with the process
(TTY), the cumulated CPU time in [dd-]hh:mm:ss format (TIME), and the
executable name (CMD). The use of BSD-style options will add process state
(STAT) to the default display. The use of BSD-style options will also change
the process selection to include processes on other terminals (TTYs) that are
owned by you; alternately, this may be described as setting the selection to
be the set of all processes filtered to exclude processes owned by other
users or not on a terminal. Output is unsorted by default.
Except as described below, process selection options are additive. The
default selection is discarded, and then the selected processes are added to
the set of processes to be displayed. A process will thus be shown if it
meets any of the selection criteria.
COMMAND-LINE OPTIONS
This version of ps accepts several kinds of options:
1 UNIX options, which may be grouped and must be preceeded by a dash.
2 BSD options, which may be grouped and must not be used with a dash.
3 GNU long options, which are preceeded by two dashes.
Options of different types may be freely mixed, but conflicts can appear.
There are some synonomous options, which are functionally identical, due to
the many standards and ps implementations that this ps is compatible with.
Note that "ps -aux" is distinct from "ps aux". The POSIX and UNIX standards
require that "ps -aux" print all processes owned by a user named "x", as well
as printing all processes that would be selected by the -a option. If the
user named "x" does not exist, this ps may interpret the command as "ps aux"
instead and print a warning. This behavior is intended to aid in
transitioning old scripts and habits. It is fragile, subject to change, and
thus should not be relied upon.
EXAMPLES
To see every process on the system using standard syntax:
ps -e
ps -ef
ps -eF
ps -ely
To see every process on the system using BSD syntax:
ps ax
ps axu
To print a process tree:
ps -ejH
ps axjf
To get info about threads:
ps -eLf
ps axms
To get security info:
ps -eo euser,ruser,suser,fuser,f,comm,label
ps axZ
ps -eM
To see every process except those running as root (real & effective ID)
ps -U root -u root -N
To see every process with a user-defined format:
ps -eo pid,tid,class,rtprio,ni,pri,psr,pcpu,stat,wchan:14,comm
ps axo stat,euid,ruid,tty,tpgid,sess,pgrp,ppid,pid,pcpu,comm
ps -eopid,tt,user,fname,tmout,f,wchan
Odd display with AIX field descriptors:
ps -o "%u : %U : %p : %a"
Print only the process IDs of syslogd:
ps -C syslogd -o pid=
Print only the name of PID 42:
ps -p 42 -o comm=
SIMPLE PROCESS SELECTION
-A Select all processes. Identical to -e.
-N Select all processes except those that fulfill the specified
conditions.
T Select all processes associated with this terminal. Identical
to the t option without any argument.
-a Select all processes except session leaders (see getsid(2))
and processes not associated with a terminal.
a Lift the BSD-style "only yourself" restriction, which is
imposed upon the set of all processes when some BSD-style
(without "-") options are used or when the ps personality
setting is BSD-like. The set of processes selected in this
manner is in addition to the set of processes selected by
other means. An alternate description is that this option
causes ps to list all processes with a terminal (tty), or to
list all processes when used together with the x option.
-d Select all processes except session leaders.
-e Select all processes. Identical to -A.
g Really all, even session leaders. This flag is obsolete and
may be discontinued in a future release. It is normally
implied by the a flag, and is only useful when operating in
the sunos4 personality.
r Restrict the selection to only running processes.
x Lift the BSD-style "must have a tty" restriction, which is
imposed upon the set of all processes when some BSD-style
options are used or when the ps personality setting is
BSD-like. The set of processes selected in this manner is in
addition to the set of processes selected by other means. An
alternate description is that this option causes ps to list
all processes owned by you (same EUID as ps), or to list all
processes when used together with the a option.
--deselect Select all processes except those that fulfill the specified
conditions.
PROCESS SELECTION BY LIST
These options accept a single argument in the form of a blank-separated or
comma-separated list. They can be used multiple times.
For example: ps -p "1 2" -p 3,4
-C cmdlist Select by command name.
This selects the processes whose executable name is given in
cmdlist.
-G grplist Select by real group ID (RGID) or name.
This selects the processes whose real group name or ID is in
the grplist list. The real group ID identifies the group of
the user who created the process, see getgid(2).
U userlist Select by effective user ID (EUID) or name.
This selects the processes whose effective user name or ID is
in userlist. The effective user ID describes the user whose
file access permissions are used by the process
(see geteuid(2)). Identical to -u and --user.
-U userlist select by real user ID (RUID) or name.
It selects the processes whose real user name or ID is in the
userlist list. The real user ID identifies the user who
created the process, see getuid(2).
-g grplist Select by session OR by effective group name.
Selection by session is specified by many standards, but
selection by effective group is the logical behavior that
several other operating systems use. This ps will select by
session when the list is completely numeric
(as sessions are). Group ID numbers will work only when some
group names are also specified. See the -s and --group
options.
p pidlist Select by process ID. Identical to -p and --pid.
-p pidlist Select by PID.
This selects the processes whose process ID numbers appear in
pidlist. Identical to p and --pid.
-s sesslist Select by session ID.
This selects the processes with a session ID specified
in sesslist.
t ttylist Select by tty. Nearly identical to -t and --tty, but can also
be used with an empty ttylist to indicate the terminal
associated with ps. Using the T option is considered cleaner
than using T with an empty ttylist.
-t ttylist Select by tty.
This selects the processes associated with the terminals
given in ttylist. Terminals (ttys, or screens for text
output) can be specified in several forms: /dev/ttyS1, ttyS1,
S1. A plain "-" may be used to select processes not attached
to any terminal.
-u userlist Select by effective user ID (EUID) or name.
This selects the processes whose effective user name or ID is
in userlist. The effective user ID describes the user whose
file access permissions are used by the process
(see geteuid(2)). Identical to U and --user.
--Group grplist Select by real group ID (RGID) or name. Identical to -G.
--User userlist Select by real user ID (RUID) or name. Identical to -U.
--group grplist Select by effective group ID (EGID) or name.
This selects the processes whose effective group name or ID
is in grouplist. The effective group ID describes the group
whose file access permissions are used by the process
(see geteuid(2)). The -g option is often an alternative
to --group.
--pid pidlist Select by process ID. Identical to -p and p.
--ppid pidlist Select by parent process ID. This selects the processes with
a parent process ID in pidlist. That is, it selects processes
that are children of those listed in pidlist.
--sid sesslist Select by session ID. Identical to -s.
--tty ttylist Select by terminal. Identical to -t and t.
--user userlist Select by effective user ID (EUID) or name. Identical to -u
and U.
-123 Identical to --sid 123.
123 Identical to --pid 123.
OUTPUT FORMAT CONTROL
These options are used to choose the information displayed by ps. The output
may differ by personality.
-F extra full format. See the -f option, which -F implies.
-O format is like -o, but preloaded with some default columns.
Identical to -o pid,format,state,tname,time,command or
-o pid,format,tname,time,cmd, see -o below.
O format is preloaded o (overloaded).
The BSD O option can act like -O (user-defined output format
with some common fields predefined) or can be used to specify
sort order. Heuristics are used to determine the behavior of
this option. To ensure that the desired behavior is obtained
(sorting or formatting), specify the option in some other way
(e.g. with -O or --sort). When used as a formatting option,
it is identical to -O, with the BSD personality.
-M Add a column of security data. (for SE Linux)
X Register format.
Z Add a column of security data. (for SE Linux)
-c Show different scheduler information for the -l option.
-f does full-format listing. This option can be combined with
many other UNIX-style options to add additional columns. It
also causes the command arguments to be printed. When used
with -L, the NLWP (number of threads) and LWP (thread ID)
columns will be added.
j BSD job control format.
-j jobs format
l display BSD long format.
-l long format. The -y option is often useful with this.
o format specify user-defined format. Identical to -o and --format.
-o format user-defined format.
format is a single argument in the form of a blank-separated
or comma-separated list, which offers a way to specify
individual output columns. The recognized keywords are
described in the STANDARD FORMAT SPECIFIERS section below.
Headers may be renamed
(ps -o pid,ruser=RealUser -o comm=Command) as desired. If all
column headers are empty (ps -o pid= -o comm=) then the
header line will not be output. Column width will increase as
needed for wide headers; this may be used to widen up columns
such as WCHAN (ps -o pid,wchan=WIDE-WCHAN-COLUMN -o comm).
Explicit width control (ps opid,wchan:42,cmd) is offered too.
The behavior of ps -o pid=X,comm=Y varies with personality;
output may be one column named "X,comm=Y" or two columns
named "X" and "Y". Use multiple -o options when in doubt. Use
the PS_FORMAT environment variable to specify a default as
desired; DefSysV and DefBSD are macros that may be used to
choose the default UNIX or BSD columns.
s display signal format
u display user-oriented format
v display virtual memory format
-y Do not show flags; show rss in place of addr. This option can
only be used with -l.
-Z display security context format (NSA SELinux, etc.)
--format format user-defined format. Identical to -o and o.
--context Display security context format. (for SE Linux)
OUTPUT MODIFIERS
-H show process hierarchy (forest)
N namelist Specify namelist file. Identical to -n, see -n above.
O order Sorting order. (overloaded)
The BSD O option can act like -O (user-defined output format
with some common fields predefined) or can be used to specify
sort order. Heuristics are used to determine the behavior of
this option. To ensure that the desired behavior is obtained
(sorting or formatting), specify the option in some other way
(e.g. with -O or --sort).
For sorting, obsolete BSD O option syntax is
O[+|-]k1[,[+|-]k2[,...]]. It orders the processes listing
according to the multilevel sort specified by the sequence of
one-letter short keys k1, k2, ... described in the OBSOLETE
SORT KEYS section below. The "+" is currently optional,
merely re-iterating the default direction on a key, but may
help to distinguish an O sort from an O format. The "-"
reverses direction only on the key it precedes.
S Sum up some information, such as CPU usage, from dead child
processes into their parent. This is useful for examining a
system where a parent process repeatedly forks off
short-lived children to do work.
c Show the true command name. This is derived from the name of
the executable file, rather than from the argv value which
could be modified by a user. Command arguments are not shown.
e Show the environment after the command.
f ASCII-art process hierarchy (forest)
h No header. (or, one header per screen in the BSD personality)
The h option is problematic. Standard BSD ps uses this option
to print a header on each page of output, but older Linux ps
uses this option to totally disable the header. This version
of ps follows the Linux usage of not printing the header
unless the BSD personality has been selected, in which case
it prints a header on each page of output. Regardless of the
current personality, you can use the long options --headers
and --no-headers to enable printing headers each page or
disable headers entirely, respectively.
k spec specify sorting order. Sorting syntax is
[+|-]key[,[+|-]key[,...]] Choose a multi-letter key from the
STANDARD FORMAT SPECIFIERS section. The "+" is optional since
default direction is increasing numerical or lexicographic
order. Identical to --sort. Examples:
ps jaxkuid,-ppid,+pid
ps axk comm o comm,args
ps kstart_time -ef
-n namelist set namelist file. Identical to N.
The namelist file is needed for a proper WCHAN display, and
must match the current Linux kernel exactly for correct
output. Without this option, the default search path for the
namelist is:
$PS_SYSMAP
$PS_SYSTEM_MAP
/proc/*/wchan
/boot/System.map-`uname -r`
/boot/System.map
/lib/modules/`uname -r`/System.map
/usr/src/linux/System.map
/System.map
n Numeric output for WCHAN and USER. (including all types of
UID and GID)
-w Wide output. Use this option twice for unlimited width.
w Wide output. Use this option twice for unlimited width.
--cols n set screen width
--columns n set screen width
--cumulative include some dead child process data (as a sum with the
parent)
--forest ASCII art process tree
--headers repeat header lines, one per page of output
--no-headers print no header line at all
--lines n set screen height
--rows n set screen height
--sort spec specify sorting order. Sorting syntax is
[+|-]key[,[+|-]key[,...]] Choose a multi-letter key from the
STANDARD FORMAT SPECIFIERS section. The "+" is optional since
default direction is increasing numerical or lexicographic
order. Identical to k. For example:
ps jax --sort=uid,-ppid,+pid
--width n set screen width
THREAD DISPLAY
H Show threads as if they were processes
-L Show threads, possibly with LWP and NLWP columns
-T Show threads, possibly with SPID column
m Show threads after processes
-m Show threads after processes
OTHER INFORMATION
L List all format specifiers.
-V Print the procps version.
V Print the procps version.
--help Print a help message.
--info Print debugging info.
--version Print the procps version.
NOTES
This ps works by reading the virtual files in /proc. This ps does not need to
be setuid kmem or have any privileges to run. Do not give this ps any special
permissions.
This ps needs access to namelist data for proper WCHAN display. For kernels
prior to 2.6, the System.map file must be installed.
CPU usage is currently expressed as the percentage of time spent running
during the entire lifetime of a process. This is not ideal, and it does not
conform to the standards that ps otherwise conforms to. CPU usage is unlikely
to add up to exactly 100%.
Programs swapped out to disk will be shown without command line arguments,
and unless the c option is given, in brackets.
The SIZE and RSS fields don't count some parts of a process including the
page tables, kernel stack, struct thread_info, and struct task_struct. This
is usually at least 20 KiB of memory that is always resident. SIZE is the
virtual size of the process (code+data+stack).
Processes marked are dead processes (so-called "zombies") that
remain because their parent has not destroyed them properly. These processes
will be destroyed by init(8) if the parent process exits.
PROCESS FLAGS
The sum of these values is displayed in the "F" column, which is provided by
the flags output specifier.
1 forked but didn't exec
4 used super-user privileges
PROCESS STATE CODES
Here are the different values that the s, stat and state output specifiers
(header "STAT" or "S") will display to describe the state of a process.
D Uninterruptible sleep (usually IO)
R Running or runnable (on run queue)
S Interruptible sleep (waiting for an event to complete)
T Stopped, either by a job control signal or because it is being traced.
W paging (not valid since the 2.6.xx kernel)
X dead (should never be seen)
Z Defunct ("zombie") process, terminated but not reaped by its parent.
For BSD formats and when the stat keyword is used, additional characters may
be displayed:
< high-priority (not nice to other users)
N low-priority (nice to other users)
L has pages locked into memory (for real-time and custom IO)
s is a session leader
l is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)
+ is in the foreground process group
OBSOLETE SORT KEYS
These keys are used by the BSD O option (when it is used for sorting). The
GNU --sort option doesn't use these keys, but the specifiers described below
in the STANDARD FORMAT SPECIFIERS section. Note that the values used in
sorting are the internal values ps uses and not the "cooked" values used in
some of the output format fields (e.g. sorting on tty will sort into device
number, not according to the terminal name displayed). Pipe ps output into
the sort(1) command if you want to sort the cooked values.
KEY LONG DESCRIPTION
c cmd simple name of executable
C pcpu cpu utilization
f flags flags as in long format F field
g pgrp process group ID
G tpgid controlling tty process group ID
j cutime cumulative user time
J cstime cumulative system time
k utime user time
m min_flt number of minor page faults
M maj_flt number of major page faults
n cmin_flt cumulative minor page faults
N cmaj_flt cumulative major page faults
o session session ID
p pid process ID
P ppid parent process ID
r rss resident set size
R resident resident pages
s size memory size in kilobytes
S share amount of shared pages
t tty the device number of the controling tty
T start_time time process was started
U uid user ID number
u user user name
v vsize total VM size in kB
y priority kernel scheduling priority
AIX FORMAT DESCRIPTORS
This ps supports AIX format descriptors, which work somewhat like the
formatting codes of printf(1) and printf(3). For example, the normal default
output can be produced with this: ps -eo "%p %y %x %c". The NORMAL codes are
described in the next section.
CODE NORMAL HEADER
%C pcpu %CPU
%G group GROUP
%P ppid PPID
%U user USER
%a args COMMAND
%c comm COMMAND
%g rgroup RGROUP
%n nice NI
%p pid PID
%r pgid PGID
%t etime ELAPSED
%u ruser RUSER
%x time TIME
%y tty TTY
%z vsz VSZ
STANDARD FORMAT SPECIFIERS
Here are the different keywords that may be used to control the output format
(e.g. with option -o) or to sort the selected processes with the GNU-style
--sort option.
For example: ps -eo pid,user,args --sort user
This version of ps tries to recognize most of the keywords used in other
implementations of ps.
The following user-defined format specifiers may contain spaces: args, cmd,
comm, command, fname, ucmd, ucomm, lstart, bsdstart, start.
Some keywords may not be available for sorting.
CODE HEADER DESCRIPTION
%cpu %CPU cpu utilization of the process in "##.#" format.
It is the CPU time used divided by the time the
process has been running (cputime/realtime ratio),
expressed as a percentage. It will not add up to
100% unless you are lucky. (alias pcpu).
%mem %MEM ratio of the process's resident set size to the
physical memory on the machine, expressed as a
percentage. (alias pmem).
args COMMAND command with all its arguments as a string. May
chop as desired. Modifications to the arguments
are not shown. The output in this column may
contain spaces. (alias cmd, command).
blocked BLOCKED mask of the blocked signals, see signal(7).
According to the width of the field, a 32-bit or
64-bit mask in hexadecimal format is displayed.
(alias sig_block, sigmask).
bsdstart START time the command started. If the process was
started less than 24 hours ago, the output format
is " HH:MM", else it is "mmm dd" (where mmm is the
three letters of the month).
bsdtime TIME accumulated cpu time, user + system. The display
format is usualy "MMM:SS", but can be shifted to
the right if the process used more than 999
minutes of cpu time.
c C integer value of the processor utilisation
percentage. (see %cpu).
caught CAUGHT mask of the caught signals, see signal(7).
According to the width of the field, a 32 or 64
bits mask in hexadecimal format is displayed.
(alias sig_catch, sigcatch).
class CLS scheduling class of the process.
(alias policy, cls). Field's possible values are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
? unknown value
cls CLS scheduling class of the process.
(alias policy, class). Field's possible values
are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
? unknown value
cmd CMD see args. (alias args, command).
comm COMMAND command name (only the executable name). The
output in this column may contain spaces.
(alias ucmd, ucomm).
command COMMAND see args. (alias args, cmd).
cp CP per-mill CPU usage. (see %cpu).
cputime TIME cumulative CPU time, "[dd-]hh:mm:ss" format.
(alias time).
egid EGID effective group ID number of the process as a
decimal integer. (alias gid).
egroup EGROUP effective group ID of the process. This will be
the textual group ID, if it can be obtained and
the field width permits, or a decimal
representation otherwise. (alias group).
eip EIP instruction pointer.
esp ESP stack pointer.
etime ELAPSED elapsed time since the process was started, in the
form [[dd-]hh:]mm:ss.
euid EUID effective user ID. (alias uid).
euser EUSER effective user name. This will be the textual
user ID, if it can be obtained and the field width
permits, or a decimal representation otherwise.
The n option can be used to force the decimal
representation. (alias uname, user).
f F flags associated with the process, see the PROCESS
FLAGS section. (alias flag, flags).
fgid FGID filesystem access group ID. (alias fsgid).
fgroup FGROUP filesystem access group ID. This will be the
textual user ID, if it can be obtained and the
field width permits, or a decimal representation
otherwise. (alias fsgroup).
flag F see f. (alias f, flags).
flags F see f. (alias f, flag).
fname COMMAND first 8 bytes of the base name of the process's
executable file. The output in this column may
contain spaces.
fuid FUID filesystem access user ID. (alias fsuid).
fuser FUSER filesystem access user ID. This will be the
textual user ID, if it can be obtained and the
field width permits, or a decimal representation
otherwise.
gid GID see egid. (alias egid).
group GROUP see egroup. (alias egroup).
ignored IGNORED mask of the ignored signals, see signal(7).
According to the width of the field, a 32-bit or
64-bit mask in hexadecimal format is displayed.
(alias sig_ignore, sigignore).
label LABEL security label, most commonly used for SE Linux
context data. This is for the Mandatory Access
Control ("MAC") found on high-security systems.
lstart STARTED time the command started.
lwp LWP lwp (light weight process, or thread) ID of the
lwp being reported. (alias spid, tid).
ni NI nice value. This ranges from 19 (nicest) to -20
(not nice to others), see nice(1). (alias nice).
nice NI see ni. (alias ni).
nlwp NLWP number of lwps (threads) in the process.
(alias thcount).
nwchan WCHAN address of the kernel function where the process
is sleeping (use wchan if you want the kernel
function name). Running tasks will display a dash
('-') in this column.
pcpu %CPU see %cpu. (alias %cpu).
pending PENDING mask of the pending signals. See signal(7).
Signals pending on the process are distinct from
signals pending on individual threads. Use the m
option or the -m option to see both. According to
the width of the field, a 32-bit or 64-bit mask in
hexadecimal format is displayed. (alias sig).
pgid PGID process group ID or, equivalently, the process ID
of the process group leader. (alias pgrp).
pgrp PGRP see pgid. (alias pgid).
pid PID process ID number of the process.
pmem %MEM see %mem. (alias %mem).
policy POL scheduling class of the process.
(alias class, cls). Possible values are:
- not reported
TS SCHED_OTHER
FF SCHED_FIFO
RR SCHED_RR
? unknown value
ppid PPID parent process ID.
psr PSR processor that process is currently assigned to.
rgid RGID real group ID.
rgroup RGROUP real group name. This will be the textual
group ID, if it can be obtained and the field
width permits, or a decimal representation
otherwise.
rss RSS resident set size, the non-swapped physical memory
that a task has used (in kiloBytes).
(alias rssize, rsz).
rssize RSS see rss. (alias rss, rsz).
rsz RSZ see rss. (alias rss, rssize).
rtprio RTPRIO realtime priority.
ruid RUID real user ID.
ruser RUSER real user ID. This will be the textual user ID,
if it can be obtained and the field width permits,
or a decimal representation otherwise.
s S minimal state display (one character). See section
PROCESS STATE CODES for the different values.
See also stat if you want additionnal information
displayed. (alias state).
sched SCH scheduling policy of the process. The policies
sched_other, sched_fifo, and sched_rr are
respectively displayed as 0, 1, and 2.
sess SESS session ID or, equivalently, the process ID of the
session leader. (alias session, sid).
sgi_p P processor that the process is currently executing
on. Displays "*" if the process is not currently
running or runnable.
sgid SGID saved group ID. (alias svgid).
sgroup SGROUP saved group name. This will be the textual
group ID, if it can be obtained and the field
width permits, or a decimal representation
otherwise.
sid SID see sess. (alias sess, session).
sig PENDING see pending. (alias pending, sig_pend).
sigcatch CAUGHT see caught. (alias caught, sig_catch).
sigignore IGNORED see ignored. (alias ignored, sig_ignore).
sigmask BLOCKED see blocked. (alias blocked, sig_block).
size SZ approximate amount of swap space that would be
required if the process were to dirty all writable
pages and then be swapped out. This number is
very rough!
spid SPID see lwp. (alias lwp, tid).
stackp STACKP address of the bottom (start) of stack for the
process.
start STARTED time the command started. If the process was
started less than 24 hours ago, the output format
is "HH:MM:SS", else it is " mmm dd" (where mmm is
a three-letter month name).
start_time START starting time or date of the process. Only the
year will be displayed if the process was not
started the same year ps was invoked, or "mmmdd"
if it was not started the same day, or "HH:MM"
otherwise.
stat STAT multi-character process state. See section PROCESS
STATE CODES for the different values meaning. See
also s and state if you just want the first
character displayed.
state S see s. (alias s).
suid SUID saved user ID. (alias svuid).
suser SUSER saved user name. This will be the textual user ID,
if it can be obtained and the field width permits,
or a decimal representation otherwise.
(alias svuser).
svgid SVGID see sgid. (alias sgid).
svuid SVUID see suid. (alias suid).
sz SZ size in physical pages of the core image of the
process. This includes text, data, and stack
space.
thcount THCNT see nlwp. (alias nlwp). number of kernel threads
owned by the process.
tid TID see lwp. (alias lwp).
time TIME cumulative CPU time, "[dd-]hh:mm:ss" format.
(alias cputime).
tname TTY controlling tty (terminal). (alias tt, tty).
tpgid TPGID ID of the foreground process group on the tty
(terminal) that the process is connected to, or -1
if the process is not connected to a tty.
tt TT controlling tty (terminal). (alias tname, tty).
tty TT controlling tty (terminal). (alias tname, tt).
ucmd CMD see comm. (alias comm, ucomm).
ucomm COMMAND see comm. (alias comm, ucmd).
uid UID see euid. (alias euid).
uname USER see euser. (alias euser, user).
user USER see euser. (alias euser, uname).
vsize VSZ virtual memory usage of entire process.
vm_lib + vm_exe + vm_data + vm_stack
vsz VSZ see vsize. (alias vsize).
wchan WCHAN name of the kernel function in which the process
is sleeping, a "-" if the process is running, or a
"*" if the process is multi-threaded and ps is not
displaying threads.
ENVIRONMENT VARIABLES
The following environment variables could affect ps:
COLUMNS
Override default display width.
LINES
Override default display height.
PS_PERSONALITY
Set to one of posix, old, linux, bsd, sun, digital...
(see section PERSONALITY below).
CMD_ENV
Set to one of posix, old, linux, bsd, sun, digital...
(see section PERSONALITY below).
I_WANT_A_BROKEN_PS
Force obsolete command line interpretation.
LC_TIME
Date format.
PS_COLORS
Not currently supported.
PS_FORMAT
Default output format override.
PS_SYSMAP
Default namelist (System.map) location.
PS_SYSTEM_MAP
Default namelist (System.map) location.
POSIXLY_CORRECT
Don't find excuses to ignore bad "features".
POSIX2
When set to "on", acts as POSIXLY_CORRECT.
UNIX95
Don't find excuses to ignore bad "features".
_XPG
Cancel CMD_ENV=irix non-standard behavior.
In general, it is a bad idea to set these variables. The one exception is
CMD_ENV or PS_PERSONALITY, which could be set to Linux for normal systems.
Without that setting, ps follows the useless and bad parts of the Unix98
standard.
PERSONALITY
390 like the S/390 OpenEdition ps
aix like AIX ps
bsd like FreeBSD ps (totally non-standard)
compaq like Digital Unix ps
debian like the old Debian ps
digital like Tru64 (was Digital Unix, was OSF/1) ps
gnu like the old Debian ps
hp like HP-UX ps
hpux like HP-UX ps
irix like Irix ps
linux ***** RECOMMENDED *****
old like the original Linux ps (totally non-standard)
os390 like OS/390 Open Edition ps
posix standard
s390 like OS/390 Open Edition ps
sco like SCO ps
sgi like Irix ps
solaris2 like Solaris 2+ (SunOS 5) ps
sunos4 like SunOS 4 (Solaris 1) ps (totally non-standard)
svr4 standard
sysv standard
tru64 like Tru64 (was Digital Unix, was OSF/1) ps
unix standard
unix95 standard
unix98 standard
SEE ALSO
top(1), pgrep(1), pstree(1), proc(5).
STANDARDS
This ps conforms to:
1 Version 2 of the Single Unix Specification
2 The Open Group Technical Standard Base Specifications, Issue 6
3 IEEE Std 1003.1, 2004 Edition
4 X/Open System Interfaces Extension [UP XSI]
5 ISO/IEC 9945:2003
AUTHOR
ps was originally written by Branko Lankester . Michael
K. Johnson re-wrote it significantly to use the proc
filesystem, changing a few things in the process. Michael Shields
added the pid-list feature. Charles Blake
added multi-level sorting, the dirent-style library, the
device name-to-number mmaped database, the approximate binary search directly
on System.map, and many code and documentation cleanups. David
Mossberger-Tang wrote the generic BFD support for psupdate. Albert Cahalan
rewrote ps for full Unix98 and BSD support, along with
some ugly hacks for obsolete and foreign syntax.
Please send bug reports to . No subscription is
required or suggested.
Linux July 28, 2004 PS(1)
UNIX/Linux commands referenced on this page: