[root@www ~]# man ps
PS(1) Linux User碵 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.
This version of ps accepts several kinds of options:
1 UNIX options, which may be grouped and must be preceded by a dash.
2 BSD options, which may be grouped and must not be used with a dash.
3 GNU long options, which are preceded by two dashes.
Options of different types may be freely mixed, but conflicts can appear. There
are some synonymous 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.
By default, ps selects all processes with the same effective user ID (euid=EUID)
as the current user and associated with the same terminal as the invoker. It
displays the process ID (pid=PID), the terminal associated with the process
(tname=TTY), the cumulated CPU time in [dd-]hh:mm:ss format (time=TIME), and the
executable name (ucmd=CMD). Output is unsorted by default.
The use of BSD-style options will add process state (stat=STAT) to the default
display and show the command args (args=COMMAND) instead of the executable name.
You can override this with the PS_FORMAT environment variable. 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. These effects are not
considered when options are described as being "identical" below, so -M will be
considered identical to Z and so on.
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
given selection criteria.
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 running as root (real & effective ID) in user format:
ps -U root -u root u
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
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. (negates the selection) Identical to --deselect.
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
(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 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. (negates the selection) Identical to -N.
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. Identical to Z. (for SE Linux)
X Register format.
Z Add a column of security data. Identical to -M. (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. See the c option, the format keyword args, and the format
keyword comm.
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 (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. Command
arguments and any modifications to them (see setproctitle(3)) are
thus not shown. This option effectively turns the args format
keyword into the comm format keyword; it is useful with the -f
format option and with the various BSD-style format options,
which all normally display the command arguments. See the -f
option, the format keyword args, and the format keyword comm.
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%.
The SIZE and RSS fields don碪 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 <defunct> 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碪 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碪 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 controlling 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. Currently,
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碵 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. Modifications to
the arguments may be shown. The output in this column may
contain spaces. A process marked <defunct> is partly dead,
waiting to be fully destroyed by its parent. Sometimes the
process args will be unavailable; when this happens, ps will
instead print the executable name in brackets.
(alias cmd, command). See also the comm format keyword, the
-f option, and the c option.
When specified last, this column will extend to the edge of
the display. If ps can not determine display width, as when
output is redirected (piped) into a file or another command,
the output width is undefined. (it may be 80, unlimited,
determined by the TERM variable, and so on) The COLUMNS
environment variable or --cols option may be used to exactly
determine the width in this case. The w or -w option may be
also be used to adjust width.
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
usually "MMM:SS", but can be shifted to the right if the
process used more than 999 minutes of cpu time.
c C processor utilization. Currently, this is the integer value
of the percent usage over the lifetime of the process.
(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碵
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碵 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). Modifications to the
command name will not be shown. A process marked <defunct> is
partly dead, waiting to be fully destroyed by its parent. The
output in this column may contain spaces.
(alias ucmd, ucomm). See also the args format keyword, the -f
option, and the c option.
When specified last, this column will extend to the edge of
the display. If ps can not determine display width, as when
output is redirected (piped) into a file or another command,
the output width is undefined. (it may be 80, unlimited,
determined by the TERM variable, and so on) The COLUMNS
environment variable or --cols option may be used to exactly
determine the width in this case. The w or -w option may be
also be used to adjust width.
command COMMAND see args. (alias args, cmd).
cp CP per-mill (tenths of a percent) 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碵 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 (皚皎 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 additional 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. Device mappings are
currently excluded; this is subject to change. See vsz and
rss.
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 see vsz. (alias vsz).
vsz VSZ virtual memory size of the process in KiB (1024-byte units).
Device mappings are currently excluded; this is subject to
change. (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. You may set this to a format string of the
type used for the -o option. The DefSysV and DefBSD values are particularly
useful.
PS_SYSMAP
Default namelist (System.map) location.
PS_SYSTEM_MAP
Default namelist (System.map) location.
POSIXLY_CORRECT
Don碪 find excuses to ignore bad "features".
POSIX2
When set to "on", acts as POSIXLY_CORRECT.
UNIX95
Don碪 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 <lankeste@fwi.uva.nl>. Michael K.
Johnson <johnsonm@redhat.com> re-wrote it significantly to use the proc
filesystem, changing a few things in the process. Michael Shields
<mjshield@nyx.cs.du.edu> added the pid-list feature. Charles Blake
<cblake@bbn.com> 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 <albert@users.sf.net>
rewrote ps for full Unix98 and BSD support, along with some ugly hacks for
obsolete and foreign syntax.
Please send bug reports to <procps-feedback@lists.sf.net>. No subscription is
required or suggested.
Linux July 28, 2004 PS(1) |
