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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               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.

       -A              Select all processes. Identical to -e.

       -a              Select all processes except both session leaders (see
                       getsid(2)) and processes not associated with a
                       terminal.

       -d              Select all processes except session leaders.

       --deselect      Select all processes except those that fulfill the
                       specified conditions. (negates the selection) Identical
                       to -N.

       -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.

       -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.

       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.

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

       -123            Identical to --sid 123.

       123             Identical to --pid 123.

       -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).

       -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.

       --Group grplist Select by real group ID (RGID) or name. Identical to
                       -G.

       --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.

       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.

       --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.

       -s sesslist     Select by session ID.
                       This selects the processes with a session ID specified
                       in sesslist.

       --sid sesslist  Select by session ID. Identical to -s.

       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.

       --tty ttylist   Select by terminal. Identical to -t and t.

       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).

       -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.

       --User userlist Select by real user ID (RUID) or name. Identical to -U.

       --user userlist Select by effective user ID (EUID) or name. Identical
                       to -u and U.

OUTPUT FORMAT CONTROL

       These options are used to choose the information displayed by ps. The
       output may differ by personality.

       -c              Show different scheduler information for the -l option.

       --context       Display security context format. (for SE Linux)

       -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.

       -F              extra full format. See the -f option, which -F implies.

       --format format user-defined format. Identical to -o and o.

       j               BSD job control format.

       -j              jobs format

       l               display BSD long format.

       -l              long format. The -y option is often useful with this.

       -M              Add a column of security data. Identical to Z.
                       (for SE Linux)

       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.

       -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        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

       X               Register format.

       -y              Do not show flags; show rss in place of addr. This
                       option can only be used with -l.

       Z               Add a column of security data. Identical to -M.
                       (for SE Linux)

OUTPUT MODIFIERS

       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
                       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.

       --cols n        set screen width

       --columns n     set screen width

       --cumulative    include some dead child process data (as a sum with the
                       parent)

       e               Show the environment after the command.

       f               ASCII-art process hierarchy (forest)

       --forest        ASCII art process tree

       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.

       -H              show process hierarchy (forest)

       --headers       repeat header lines, one per page of output

       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

       --lines n       set screen height

       n               Numeric output for WCHAN and USER. (including all types
                       of UID and GID)

       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.

       --no-headers    print no header line at all. --no-heading is an alias
                       for this option.

       --rows n        set screen height

       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.

       --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

       w               Wide output. Use this option twice for unlimited width.

       -w              Wide output. Use this option twice for unlimited width.

       --width n       set screen width

THREAD DISPLAY

       H               Show threads as if they were processes

       -L              Show threads, possibly with LWP and NLWP columns

       m               Show threads after processes

       -m              Show threads after processes

       -T              Show threads, possibly with SPID column

OTHER INFORMATION

       --help          Print a help message.

       --info          Print debugging info.

       L               List all format specifiers.

       V               Print the procps version.

       -V              Print the procps version.

       --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.

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 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’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 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). See also lstart, start,
                          start_time, and stime.

       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’s possible values are:
                          -   not reported
                          TS  SCHED_OTHER
                          FF  SCHED_FIFO
                          RR  SCHED_RR
                          B   SCHED_BATCH
                          ISO SCHED_ISO
                          IDL SCHED_IDLE
                          ?   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
                          B   SCHED_BATCH
                          ISO SCHED_ISO
                          IDL SCHED_IDLE
                          ?   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’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. See also bsdstart, start,
                          start_time, and stime.

       lwp        LWP     lwp (light weight process, or thread) ID of the lwp
                          being reported. (alias spid, tid).

       maj_flt    MAJFLT  The number of major page faults that have occured
                          with this process.

       min_flt    MINFLT  The number of minor page faults that have occured
                          with this process.

       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
                          B   SCHED_BATCH
                          ISO SCHED_ISO
                          IDL SCHED_IDLE
                          ?   unknown value

       ppid       PPID    parent process ID.

       pri        PRI     priority of the process. Higher number means lower
                          priority

       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_NORMAL), SCHED_FIFO, SCHED_RR,
                          SCHED_BATCH, SCHED_ISO, and SCHED_IDLE are
                          respectively displayed as 0, 1, 2, 3, 4, and 5.

       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       SIZE    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). See also lstart, bsdstart,
                          start_time, and stime.

       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. See also
                          bsdstart, start, lstart, and stime.

       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).

       supgid     SUPGID  gid of supplementary groups, see getgroups(2).

       supgrp     SUPGRP  names of supplementary groups, see getgroups(2).

       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’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 <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.