ps

ps -Process status

any time the system is running, processes are also running. You can use the ps command to find out which processes are running and display information about those processes.

The ps command has several flags that enable you to specify which processes to list and what information to display about each process.

To show all processes running on your system, at the prompt, type the following:

ps -ef
The system displays information similar to the following:

    USER   PID  PPID   C    STIME    TTY  TIME CMD
    root     1     0   0   Jun 28      -  3:23 /etc/init 
    root  1588  6963   0   Jun 28      -  0:02 /usr/etc/biod 6 
    root  2280     1   0   Jun 28      -  1:39 /etc/syncd 60 
    mary  2413 16998   2 07:57:30      -  0:05 aixterm 
    mary 11632 16998   0 07:57:31  lft/1  0:01 xbiff 
    mary 16260  2413   1 07:57:35  pts/1  0:00 /bin/ksh 
    mary 16469     1   0 07:57:12  lft/1  0:00 ksh /usr/lpp/X11/bin/xinit 
    mary 19402 16260  20 09:37:21  pts/1  0:00 ps -ef 

The columns in the previous output are defined as follows:

Item Description
USER User login name
PID Process ID
PPID Parent process ID
C CPU utilization of process
STIME Start time of process
TTY Controlling workstation for the process
TIME Total execution time for the process
CMD Command

In the previous example, the process ID for the

ps -ef command is 19402.

Its parent process ID is 16260, the/bin/ksh command.

If the listing is very long, the top portion scrolls off the screen. To display the listing one page (screen) at a time, pipe the ps command to the pg command. At the prompt, type the following:

ps -ef | pg
To display status information of all processes running on your system, at the prompt, type the following:

ps gv
This form of the command lists a number of statistics for each active process. Output from this command looks similar to the following:

   PID    TTY STAT  TIME PGIN  SIZE   RSS   LIM  TSIZ   TRS %CPU %MEM COMMAND
     0      - A     0:44    7     8     8    xx     0     0  0.0  0.0 swapper
     1      - A     1:29  518   244   140    xx    21    24  0.1  1.0 /etc/init
   771      - A     1:22    0    16    16    xx     0     0  0.0  0.0 kproc
  1028      - A     0:00   10    16     8    xx     0     0  0.0  0.0 kproc
  1503      - A     0:33  127    16     8    xx     0     0  0.0  0.0 kproc
  1679      - A     1:03  282   192    12 32768   130     0  0.7  0.0 pcidossvr
  2089      - A     0:22  918    72    28    xx     1     4  0.0  0.0 /etc/sync
  2784      - A     0:00    9    16     8    xx     0     0  0.0  0.0 kproc
  2816      - A     5:59 6436  2664   616     8   852   156  0.4  4.0 /usr/lpp/
  3115      - A     0:27  955   264   128    xx    39    36  0.0  1.0 /usr/lib/
  3451      - A     0:00    0    16     8    xx     0     0  0.0  0.0 kproc
  3812      - A     0:00   21   128    12 32768    34     0  0.0  0.0 usr/lib/lpd/
  3970      - A     0:00    0    16     8    xx     0     0  0.0  0.0 kproc
  4267      - A     0:01  169   132    72 32768    16    16  0.0  0.0 /etc/sysl
  4514  lft/0 A     0:00   60   200    72    xx    39    60  0.0  0.0 /etc/gett
  4776  pts/3 A     0:02  250   108   280     8   303   268  0.0  2.0 -ksh 
  5050      - A     0:09 1200   424   132 32768   243    56  0.0  1.0 /usr/sbin
  5322      - A     0:27 1299   156   192    xx    24    24  0.0  1.0 /etc/cron
  5590      - A     0:00    2   100    12 32768    11     0  0.0  0.0 /etc/writ
  5749      - A     0:00    0   208    12    xx    13     0  0.0  0.0 /usr/lpp/
  6111      - T     0:00   66   108    12 32768    47     0  0.0  0.0 /usr/lpp/

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

       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).

       -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

       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.

       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)

                       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
                            $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

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'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 <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.

       If the length of the username is greater than the length of the display
       column, the numeric user ID is displayed instead.

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

       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 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
       %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’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. 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

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'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). 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

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).
                    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

                    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


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.

       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