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TLDR: ps (tldr-pages)

Information about running processes.

  • List all running processes
    ps aux
  • List all running processes including the full command string
    ps auxww
  • Search for a process that matches a string (the brackets will prevent `grep` from matching itself)
    ps aux | grep {{s]tring}}
  • List all processes of the current user in extra full format
    ps {{-u|--user}} $(id {{-u|--user}}) -F
  • List all processes of the current user as a tree
    ps {{-u|--user}} $(id {{-u|--user}}) f
  • Get the parent PID of a process
    ps {{-o|--format}} ppid= {{-p|--pid}} {{pid}}
  • Sort processes by memory consumption
    ps --sort size
PS(1)                                       User Commands                                      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 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 -Ao pid,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 -q 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 --pid 123.

       123    Identical to --pid 123.

       -C cmdlist
              Select by command name.  This selects the processes whose executable name is given in
              cmdlist.  NOTE: The command name is not the same as the command line. Previous
              versions of procps and the kernel truncated this command name to 15 characters. This
              limitation is no longer present in both. If you depended on matching only 15
              characters, you may no longer get a match.

       -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 grplist.  The effective group ID describes the group
              whose file access permissions are used by the process (see getegid(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.

       q pidlist
              Select by process ID (quick mode).  Identical to -q and --quick-pid.

       -q pidlist
              Select by PID (quick mode).  This selects the processes whose process ID numbers
              appear in pidlist.  With this option ps reads the necessary info only for the pids
              listed in the pidlist and doesn't apply additional filtering rules.  The order of pids
              is unsorted and preserved.  No additional selection options, sorting and forest type
              listings are allowed in this mode.  Identical to q and --quick-pid.

       --quick-pid pidlist
              Select by process ID (quick mode).  Identical to -q and q.

       -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 SELinux).

       -f     Do 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 SELinux).

       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
              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 SELinux).

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

       --lines n
              Set screen height.

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

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

       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.

       --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 section
              Print a help message.  The section argument can be one of simple, list, output,
              threads, misc, or all.  The argument can be shortened to one of the underlined letters
              as in: s|l|o|t|m|a.

       --info Print debugging info.

       L      List all format specifiers.

       V      Print the procps-ng version.

       -V     Print the procps-ng version.

       --version
              Print the procps-ng 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.

       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 username
       will be truncated.  See the -o and -O formatting options to customize length.

       Commands options such as ps -aux are not recommended as it is a confusion of two different
       standards.  According to the POSIX and UNIX standards, the above command asks to display all
       processes with a TTY (generally the commands users are running) plus all processes owned by a
       user named x.  If that user doesn't exist, then ps will assume you really meant ps aux.

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)
               I    Idle kernel thread
               R    running or runnable (on run queue)
               S    interruptible sleep (waiting for an event to complete)
               T    stopped by job control signal
               t    stopped by debugger during the tracing
               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 KiB
       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 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:SS" (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).

       cgname      CGNAME    display name of control groups to which the process belongs.

       cgroup      CGROUP    display control groups to which the process belongs.

       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
                                      DLN SCHED_DEADLINE
                                      ?   unknown value

       cls         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
                                      DLN SCHED_DEADLINE
                                      ?   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, command).

       cp          CP        per-mill (tenths of a percent) CPU usage.  (see %cpu).

       cputime     TIME      cumulative CPU time, "[DD-]hh:mm:ss" format.  (alias time).

       cputimes    TIME      cumulative CPU time in seconds (alias times).

       drs         DRS       data resident set size, the amount of physical memory devoted to other
                             than executable code.

       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.

       etimes      ELAPSED   elapsed time since the process was started, in seconds.

       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).

       exe         EXE       path to the executable. Useful if path cannot be printed via cmd, comm
                             or args format options.

       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 group 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 or 64 bits mask in hexadecimal format is displayed.
                             (alias sig_ignore, sigignore).

       ipcns       IPCNS     Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       label       LABEL     security label, most commonly used for SELinux 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.

       lsession    SESSION   displays the login session identifier of a process, if systemd support
                             has been included.

       luid        LUID      displays Login ID associated with a process.

       lwp         LWP       light weight process (thread) ID of the dispatchable entity (alias
                             spid, tid).  See tid for additional information.

       lxc         LXC       The name of the lxc container within which a task is running.  If a
                             process is not running inside a container, a dash ('-') will be shown.

       machine     MACHINE   displays the machine name for processes assigned to VM or container, if
                             systemd support has been included.

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

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

       mntns       MNTNS     Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       netns       NETNS     Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       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).

       numa        NUMA      The node associated with the most recently used processor.  A -1 means
                             that NUMA information is unavailable.

       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.

       ouid        OWNER     displays the Unix user identifier of the owner of the session of a
                             process, if systemd support has been included.

       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 or 64 bits 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       a number representing the process ID (alias tgid).

       pidns       PIDNS     Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       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
                                      DLN SCHED_DEADLINE
                                      ?   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,
                             SCHED_IDLE and SCHED_DEADLINE are respectively displayed as 0, 1, 2, 3,
                             4, 5 and 6.

       seat        SEAT      displays the identifier associated with all hardware devices assigned
                             to a specific workplace, if systemd support has been included.

       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!

       slice       SLICE     displays the slice unit which a process belongs to, if systemd support
                             has been included.

       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).

       stime       STIME     see start_time. (alias start_time).

       suid        SUID      saved user ID.  (alias svuid).

       supgid      SUPGID    group ids of supplementary groups, if any.  See getgroups(2).

       supgrp      SUPGRP    group names of supplementary groups, if any.  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.

       tgid        TGID      a number representing the thread group to which a task belongs (alias
                             pid).  It is the process ID of the thread group leader.

       thcount     THCNT     see nlwp.  (alias nlwp).  number of kernel threads owned by the
                             process.

       tid         TID       the unique number representing a dispatchable entity (alias lwp, spid).
                             This value may also appear as: a process ID (pid); a process group ID
                             (pgrp); a session ID for the session leader (sid); a thread group ID
                             for the thread group leader (tgid); and a tty process group ID for the
                             process group leader (tpgid).

       time        TIME      cumulative CPU time, "[DD-]HH:MM:SS" format.  (alias cputime).


       times       TIME      cumulative CPU time in seconds (alias cputimes).

       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.

       trs         TRS       text resident set size, the amount of physical memory devoted to
                             executable code.

       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).

       unit        UNIT      displays unit which a process belongs to, if systemd support has been
                             included.

       user        USER      see euser.  (alias euser, uname).

       userns      USERNS    Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       utsns       UTSNS     Unique inode number describing the namespace the process belongs to.
                             See namespaces(7).

       uunit       UUNIT     displays user unit which a process belongs to, if systemd support has
                             been included.

       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.

       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 OS/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
       pgrep(1), pstree(1), top(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 AT fwi.nl⟩.  Michael K. Johnson
       ⟨johnsonm AT redhat.com⟩ re-wrote it significantly to use the proc filesystem, changing a few
       things in the process.  Michael Shields ⟨mjshield AT nyx.edu⟩ added the pid-list feature.
       Charles Blake ⟨cblake AT bbn.com⟩ added multi-level sorting, the dirent-style library, the de‐
       vice 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 sup‐
       port for psupdate.  Albert Cahalan ⟨albert AT users.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 AT freelists.org⟩.  No subscription is required or suggested.



procps-ng                                    2020-06-04                                        PS(1)
ps
NAME SYNOPSIS DESCRIPTION EXAMPLES SIMPLE PROCESS SELECTION
-A Select all processes. Identical to -e. -a Select all processes except both session leaders (see getsid(2)) and processes not -d Select all processes except session leaders. --deselect -e Select all processes. Identical to -A. -N Select all processes except those that fulfill the specified conditions (negates the
PROCESS SELECTION BY LIST
-C cmdlist -G grplist -g grplist -p pidlist -q pidlist -s sesslist -t ttylist -U userlist -u userlist
OUTPUT FORMAT CONTROL
-c Show different scheduler information for the -l option. --context -f Do full-format listing. This option can be combined with many other UNIX-style -F Extra full format. See the -f option, which -F implies. -j Jobs format. -l Long format. The -y option is often useful with this. -M Add a column of security data. Identical to Z (for SELinux). -O format -o format -y Do not show flags; show rss in place of addr. This option can only be used with -l.
OUTPUT MODIFIERS
--cumulative --forest -H Show process hierarchy (forest). --headers --no-headers -w Wide output. Use this option twice for unlimited width.
THREAD DISPLAY
-L Show threads, possibly with LWP and NLWP columns. -m Show threads after processes. -T Show threads, possibly with SPID column.
OTHER INFORMATION
-V Print the procps-ng version. --version
NOTES PROCESS FLAGS PROCESS STATE CODES OBSOLETE SORT KEYS AIX FORMAT DESCRIPTORS STANDARD FORMAT SPECIFIERS ENVIRONMENT VARIABLES PERSONALITY SEE ALSO STANDARDS AUTHOR

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