[shell cmd] ps : 프로세스 확인

현재 사용중인 프로세서 들이 어떤 것이 있는지 확인하는 명령어 이다

$ ps

  PID TTY          TIME CMD

 2803 pts/0    00:00:00 ps

 9517 pts/0    00:00:03 bash

-------------------$ man ps-----------------------------------

PS(1)                                                                           Linux User's Manual                                                                          PS(1)

NAME

       ps - report a snapshot of the current processes.

SYNOPSIS

       ps [options]

DESCRIPTION

       ps displays information about a selection of the active processes. If you want a repetitive update of the selection and the displayed information, use top(1) instead.

       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 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.

       -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              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 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       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 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).

       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

                          ?   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 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).

       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 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     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 "  <mm 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 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

       top(1), pgrep(1), pstree(1), proc(5).

STANDARDS

       This ps conforms to:

       1   Version 2 of the Single Unix Specification

       2   The Open Group Technical Standard Base Specifications, Issue 6

       3   IEEE Std 1003.1, 2004 Edition

       4   X/Open System Interfaces Extension [UP XSI]

       5   ISO/IEC 9945:2003

AUTHOR

       ps was originally written by Branko Lankester <lankeste@fwi.uva.nl>. Michael K. Johnson <johnsonm@redhat.com> re-wrote it significantly to use the proc filesystem,

       changing a few things in the process. Michael Shields <mjshield@nyx.cs.du.edu> added the pid-list feature. Charles Blake <cblake@bbn.com> added multi-level sorting, the

       dirent-style library, the device name-to-number mmaped database, the approximate binary search directly on System.map, and many code and documentation cleanups. David

       Mossberger-Tang wrote the generic BFD support for psupdate. Albert Cahalan <albert@users.sf.net> rewrote ps for full Unix98 and BSD support, along with some ugly hacks for

       obsolete and foreign syntax.

       Please send bug reports to <procps-feedback@lists.sf.net>. No subscription is required or suggested.

Linux                                                                            February 25, 2010                                                                           PS(1)