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ps(1) [osf1 man page]

ps(1)							      General Commands Manual							     ps(1)

NAME
ps - Displays current process status SYNOPSIS
Syntax conforming to XCU5.0 ps [-aAdejflm] [-o specifier] [=header] ,... [-O specifier] [=header] ,... [-g glist] [-G glist] [-p plist] [-s slist] [-t tlist] [-u ulist] [-U ulist] [-n nlist] BSD Compatible Syntax ps [aAeghjlLmsSTuvwx] [o specifier] [=header] ,... [O specifier] [=header] ,... [t tty] [process_number] The ps command displays the current process status. STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: ps: XCU5.0 Refer to the standards(5) reference page for more information about industry standards and associated tags. OPTIONS
Current Syntax The following options can be used with ps: Prints information to standard output about all processes, except the session leaders and pro- cesses not associated with a terminal. Writes information for all processes. Prints information to standard output about all processes, except the session leaders. Prints information to standard output about all processes. Equivalent to -A. Generates a full listing. Prints only information about processes that are in the process groups listed in glist. The glist is a list of process-group identifiers enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces (or tabs), or both. Because of the way the shell treats spaces and tabs, you need to quote space-separated lists. Writes information for processes whose real group ID numbers or names are given in glist. The glist is a list of process-group identifiers enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces (or tabs), or both. Because of the way the shell treats spaces and tabs, you need to quote space-sepa- rated lists. [Tru64 UNIX] Produces job control information, with fields specified for user, pid, ppid, pgid, sess, jobc, state, tname, time and command. Generates a long listing. [Tru64 UNIX] Prints all threads in a task, if the task has more than one. Specifies a list of format specifiers to describe the output format. Multiple -o options may be specified. The final output is a concatenation of all options specified. [Tru64 UNIX] If the -O option is used with one or more -o options, the -O option must appear first on the command line. [Tru64 UNIX] Same as the -o option, except it displays the fields specified by pid, state, tname, time, and command in addition to the specifiers supplied on the command line. [Tru64 UNIX] The -O option may be used with one or more -o options. The result is a concatenated output. The -O option must be specified first. Historically, used to specify an alternative system file name list, nlist, in place of the default. [Tru64 UNIX] The name list concept (see the nlist(3) reference page) does not apply to the Tru64 UNIX ps command; consequently, the -n option is ignored. Displays only information about processes with the process numbers specified in plist. The plist argument is either a list of process ID numbers or a list of process ID numbers enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces (or tabs), or both. Because of the way the shell treats spaces and tabs, you need to quote space- separated lists. [Tru64 UNIX] Enables warning messages. [Tru64 UNIX] Displays information about processes belonging to the ses- sions specified in slist. The slist argument is either a list of session ID numbers or a list of session ID numbers enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces (or tabs), or both. Because of the way the shell treats spaces and tabs, you need to quote space-separated lists. Displays only information about processes associated with the ter- minals listed in tlist. The tlist argument is either a list of terminal identifiers or a list of terminal identifiers enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces, or both. Because of the way the shell treats spaces and tabs, you need to quote space-separated lists. Terminal identifiers must be in one of two forms: The device's file name The device's digit identifier, if the device's file name begins with tty Displays only information about processes with the user ID numbers or login names specified in ulist. The ulist argument is either a list of user IDs or a list of user IDs enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces, or both. Because of the way the shell treats spaces and tabs, you need to quote space-separated lists. In the listing, ps displays the numerical user ID unless the -f option is used; then it displays the login name. Writes information for processes whose real user ID numbers or login names are given in ulist. The ulist argument is either a list of user IDs or a list of user IDs enclosed in " " (double quotes) and separated from one another by a comma or one or more spaces, or both. Because of the way the shell treats spaces and tabs, you need to quote space-separated lists. BSD Compatible Syntax [Tru64 UNIX] The following BSD compatible options can be used with ps (note that these options are not prefixed with a - (dash) charac- ter): [Tru64 UNIX] Asks for information regarding processes associated with terminals (ordinarily only one's own processes are displayed). [Tru64 UNIX] Increases the argument space. [Tru64 UNIX] Asks for the environment to be printed, as well as the arguments to the command. [Tru64 UNIX] Asks for all processes. Without this option, ps only prints interesting processes. Processes are deemed to be uninteresting if they are process group leaders. This normally eliminates top-level command interpreters and processes waiting for users to log in on free terminals. [Tru64 UNIX] Repeats the header after each screenful of information. [Tru64 UNIX] Produces job control information, with fields specified by user, ppid, pgid, sess, and jobc. [Tru64 UNIX] Asks for a detailed list, with fields specified by ppid, cp, pri, nice, vsize, rssize and wchan. [Tru64 UNIX] Lists all available format specifiers. [Tru64 UNIX] Prints all threads in a task, if the task has more than one. [Tru64 UNIX] Specifies a list of format specifiers to describe the output format. [Tru64 UNIX] Same as o, except it displays the fields specified by pid, state, tname, cputime, and comm in addition to the specifiers supplied on the command line. [Tru64 UNIX] Gives signal states of the processes, with fields specified by uid, cursig, sig, sigmask, sigignore, and sigcatch. [Tru64 UNIX] Prints usage summaries (total usage of a command, as opposed to current usage). [Tru64 UNIX] Lists only processes for the speci- fied terminal. [Tru64 UNIX] Lists all processes on your terminal. [Tru64 UNIX] Produces a user oriented output. This includes fields specified by user, pcpu, pmem, vsize, rssize, and start. [Tru64 UNIX] Produces a version of the output containing virtual memory statis- tics. This includes fields specified by cputime, sl, pagein, vsize, rssize, pcpu, and pmem. [Tru64 UNIX] Uses a wide output format (132 columns (bytes) rather than 80); if this option is doubled (ww), uses an arbitrarily wide output. This information determines how much of long commands to print. [Tru64 UNIX] Asks even about processes with no terminal. OPERANDS
Current Syntax None BSD Compatible Syntax [Tru64 UNIX] Restricts output to the specified process. This argument must be entered last on the command line. DESCRIPTION
While ps is a fairly accurate snapshot of the system, ps cannot begin and finish a snapshot as fast as some processes change state. At times there may be minor discrepancies. The ps command can be used on multiprocessing systems and for querying the system state of realtime applications for their POSIX priority and scheduling policy. Output formats for each process include the process ID (pid), control terminal of the process (tname), CPU time used by the process (cputime) (this includes both user and system time), the state of the process (state), and an indication of the command that is running (command). The abbreviation tty indicates a terminal. [Tru64 UNIX] The state is given by a sequence of letters, for example, RWN. The first letter indicates the status of the process: [Tru64 UNIX] Runnable process. [Tru64 UNIX] Uninterruptible sleeping process. [Tru64 UNIX] Process sleeping for less than about 20 seconds. [Tru64 UNIX] Idle (sleeping longer than about 20 seconds) process. [Tru64 UNIX] Stopped process. [Tru64 UNIX] Halted process. [Tru64 UNIX] Additional characters after these, if any, indicate additional state information: [Tru64 UNIX] Process is swapped out (shows a blank space if the process is loaded (in-core)). [Tru64 UNIX] Process has specified a soft limit on memory requirements and is exceed- ing that limit; such a process is (necessarily) not swapped. [Tru64 UNIX] An additional letter may indicate whether a process is running with altered CPU scheduling priority (nice): [Tru64 UNIX] Process priority is reduced. [Tru64 UNIX] Process priority has been artificially raised. [Tru64 UNIX] Process is a process group leader with a controlling terminal. Format Specifiers The following list contains all format specifiers that can be used with ps: ----------------------------------------------------------------- Specifier Header Meaning ----------------------------------------------------------------- acflag ACFLG [Tru64 UNIX] Process accounting flag args COMMAND Command arguments c C CPU utilization factor for scheduling cmd CMD [Tru64 UNIX] Command arguments comm COMMAND Command name for accounting command COMMAND [Tru64 UNIX] Command arguments (and envi- ronment with BSD e option) cp CP [Tru64 UNIX] Short-term CPU utilization factor (used in scheduling) cputime TIME [Tru64 UNIX] Current CPU time used cursig CURSIG [Tru64 UNIX] Current signal etime ELAPSED Time command has been running flag F [Tru64 UNIX] Process flags group GROUP Group name inblock INBLK [Tru64 UNIX] Block input operations jobc JOBC [Tru64 UNIX] Current count of processes qualifying PGID for job control logname LOGNAME [Tru64 UNIX] User's login name longtname TTY [Tru64 UNIX] Long controlling terminal device name lstart STARTED [Tru64 UNIX] Start date and time of process majflt MAJFLT [Tru64 UNIX] Page faults minflt MINFLT [Tru64 UNIX] Page reclaims msgrcv MSGRCV [Tru64 UNIX] Messages received msgsnd MSGSND [Tru64 UNIX] Messages sent nice NI Process scheduling increment (see the set- priority() call). nivcsw IVCSW [Tru64 UNIX] Involuntary context switches nsignals NSIGS [Tru64 UNIX] Signals received nswap NSWAP [Tru64 UNIX] Swaps nvcsw VCSW [Tru64 UNIX] Voluntary context switches nwchan WCHAN [Tru64 UNIX] Address of event on which a process is waiting (an address in the sys- tem). In this case, the initial part of the address is trimmed off and is printed hexadecimally, for example, 0x80004000 prints as 4000. oublock OUBLK [Tru64 UNIX] Block output operations pagein PAGEIN [Tru64 UNIX] Number of disk I/Os result- ing from references by the process to pages not loaded in core. pcpu %CPU Percent CPU usage. This is a decaying average of up to a minute of previous (real) time. Since the time base over which this is computed varies (since pro- cesses may be very young), it is possible for the sum of all %CPU fields to exceed 100%. pgid PGID Process group ID pid PID Process ID pmem %MEM [Tru64 UNIX] Percent real memory usage policy POL [Tru64 UNIX] Current scheduling policy ppid PPID Parent process ID pri PRI [Tru64 UNIX] Process priority pset PSET [Tru64 UNIX] Current processor set (^ means bound) psr PSR [Tru64 UNIX] Current processor (~ means bound) psxpri PPR [Tru64 UNIX] POSIX scheduling priority rgid RGID [Tru64 UNIX] Process group (real GID) rgroup RGROUP Real group name rssize RSS [Tru64 UNIX] Real memory (resident set) size of the process (in 1024 byte units) ruid RUID [Tru64 UNIX] Process user ID (real UID) ruser RUSER User ID scount SCNT [Tru64 UNIX] Suspend count sess SESS [Tru64 UNIX] Session ID sig PENDING [Tru64 UNIX] Signals pending to this process sigcatch CAUGHT [Tru64 UNIX] Signals being caught sigignore IGNORED [Tru64 UNIX] Signals being ignored sigmask BLOCKED [Tru64 UNIX] Current signal mask sl SL [Tru64 UNIX] Sleep time start STARTED [Tru64 UNIX] Start time of process. If start time was more than 24 hours ago, gives the date. state S [Tru64 UNIX] Symbolic process status status STATUS [Tru64 UNIX] Process status stime STARTED Start time of process. If start time was more than 24 hours ago, gives the date. svgid SVGID [Tru64 UNIX] Saved process group ID svuid SVUID [Tru64 UNIX] Saved process user ID systime SYSTEM [Tru64 UNIX] Time spent in system tdev TDEV [Tru64 UNIX] Major/minor device for con- trolling terminal time TIME Current CPU time used tname TTY [Tru64 UNIX] Controlling terminal device name tpgid TPGID [Tru64 UNIX] Foreground process group associated with terminal tsession TSESS [Tru64 UNIX] Session associated with ter- minal tt TTY Controlling terminal device name tty TTY Controlling terminal device name ucomm COMMAND [Tru64 UNIX] Command name for accounting uid UID [Tru64 UNIX] Process user ID (effective UID) umask UMASK [Tru64 UNIX] Process umask user USER Username usertime USER [Tru64 UNIX] Time spent in user space usrpri UPR [Tru64 UNIX] Base scheduling priority u_procp UPROCP [Tru64 UNIX] Address of process in user area vsize VSZ [Tru64 UNIX] Process virtual address size vsz VSZ Process virtual address size wchan WCHAN [Tru64 UNIX] Address of event on which a process is waiting (an address in the sys- tem). A symbol is chosen that classifies the address, if available, from the sys- tem; otherwise, it is printed numerically. ----------------------------------------------------------------- Compound Format Specifiers [Tru64 UNIX] Compound format specifiers are made up of groups of individual format specifiers, as follows: ------------------------------------------------------------------------------ Specifier Meaning ------------------------------------------------------------------------------ RUSAGE [Tru64 UNIX] minflt, majflt, nswap, inblock, oublock, msgsnd, msgrcv, nsigs, nvcsw, nivcsw THREAD [Tru64 UNIX] user, pcpu, pri, scnt, wchan, usertime, systime DFMT (default printing format) [Tru64 UNIX] pid, tname, state, cputime, command LFMT (BSD l format) [Tru64 UNIX] uid, pid, ppid, cp, pri, nice, vsz, rss, wchan, state, tname, cputime, command JFMT (j format) [Tru64 UNIX] user, pid, ppid, pgid, sess, jobc, state, tname, cputime, command SFMT (BSD s format) [Tru64 UNIX] uid, pid, cursig, sig, sigmask, sigignore, sigcatch, stat, tname, command VFMT (BSD v format) [Tru64 UNIX] pid, tt, state, time, sl, pagein, vsz, rss, pcpu, pmem, command UFMT (BSD u format) [Tru64 UNIX] uname, pid, pcpu, pmem, vsz, rss, tt, state, start, time, command F5FMT (f format) [Tru64 UNIX] uname, pid, ppid, pcpu, start, tt, time, command L5FMT (l format) [Tru64 UNIX] f, state, uid, pid, ppid, pcpu, pri, nice, rss, wchan, tt, time, ucomm FL5FMT (lf format) [Tru64 UNIX] f, state, uid, pid, ppid, pcpu, pri, nice, rss, wchan, start, time, command SCHED [Tru64 UNIX] user, pcpu, pri, usr- pri, nice, psxpri, psr, policy, pset ------------------------------------------------------------------------------ Process Flags The flags associated with process in <sys/proc.h> are as follows: ------------------------------------------------------------------------ Symbolic Con- Flag Value Meaning stant ------------------------------------------------------------------------ SLOAD 0x00000001 In core SSYS 0x00000002 [Tru64 UNIX] Swapper or pager process SLOMAP 0x00000004 Process allowed to use low virtual memory SNOTASK 0x00000040 Process completed exit SWWAIT 0x00000080 Thread is removing zombie SOMASK 0x00000200 Restore old mask after taking signal SWEXIT 0x00000400 Working on exiting SPHYSIO 0x00000800 Doing physical I/O SVFORK 0x00001000 Process resulted from vfork() SPAGV 0x00008000 Init data space on demand, from vnode SSEQL 0x00010000 User warned of sequential vm behavior SUANOM 0x00020000 User warned of random vm behavior SCONTIGN 0x00040000 Process is ignoring SIGCONT S1170 0X00080000 Process is using Single UNIX(R) Specifi- cation signal behaviors SLOGIN 0x00400000 Process marked as a login for Capacity Limitation SCTTY 0x00800000 Process has a controlling terminal SXONLY 0x02000000 Process image read-protected SAIO 0x08000000 Process performed asynchronous I/O SNOCLDWAIT 0x20000000 No zombies when children exist SNOCLDSTOP 0x40000000 No SIGCHLD when children stop SEXEC 0x80000000 Process called exec ------------------------------------------------------------------------ A process that has exited but whose parent process has not waited for it. [Tru64 UNIX] A process for which user area information could not be obtained due to a shortage of system memory. A process that is blocked trying to exit. NOTES
[Tru64 UNIX] The following BSD compatible options are not supported. (You can reconstruct the output of these options by using the appro- priate format specifiers, however.) [Tru64 UNIX] Displays the command name, as stored internally in the system for purposes of account- ing, rather than the command arguments, which are kept in the process's address space. [Tru64 UNIX] Displays numeric output. In a long listing, the wchan field is printed numerically rather than symbolically. In a user listing, the user field is replaced by a uid field. The arguments displayed by args and command format specifiers reflect the arguments passed to the command at its invocation. Any modifica- tion made to the arguments by the running command are not available. The arguments displayed by args and command format specifiers are the only output fields that contain embedded blanks, which may be a concern if the output is passed to some type of parser. Since output fields appear in the order of the format specifiers on the command line, you should put these specifiers at the end of the command if you are using a parser to analyze the output. RESTRICTIONS
[Tru64 UNIX] When you enter a ps command while running an application that forks child processes, you might see some child processes listed as being in the <defunct> state after they have exited. Processes in this state cannot be killed until the process that forked them is killed. [Tru64 UNIX] The system puts exiting child processes in the <defunct> state if their parent process is still running and has not caught the SIGCHLD signal or executed a wait() system call. [Tru64 UNIX] To avoid having users encounter this problem when they run your application, make sure that your program logic either catches the SIGCHLD signal or executes a wait() system call when spawning a child process. [Tru64 UNIX] It is an error to use two format specifiers, such as comm and ucomm or command and args that are really synonyms for the same output request. [Tru64 UNIX] It is an error to use two or more compound format specifiers that contain the same simple format specifier, or to use a sim- ple format specifier with a compound format specifier that includes the simple specifier. EXIT STATUS
The following exit values are returned: Successful completion. An error occurred. EXAMPLES
To list all your processes, enter: ps To list all processes, enter: ps -A The BSD equivalent looks like this: ps ax To list processes owned by specific users, enter: ps -f -l -ujim,jane,su To list processes associated with a specific terminal, enter: ps -t console The BSD equivalent looks like this: ps tco To display only the pid, user, and comm information for all processes, enter: ps -o pid,user,comm -A To display the parent process ID under the header PARENT, as well as the default headers (fields specified by pid, state, tname, time, command), enter: ps -O ppid=PARENT The following ps command shows the use of the SCHED specifier on a two-pro- cessor system with two processor sets: ps -O SCHED PID USER %CPU PRI UPR NI PPR PSR POL PSET S TTY TIME COM 458 root 0.0 43 44 0 20 0 TS 0 I + console 0:01.34 csh 561 root 0.0 44 44 0 19 0 TS 0 I ttyp0 0:00.42 csh 567 root 0.0 44 44 0 19 1 TS ^2 I ttyp0 0:00.03 runon 568 root 0.0 44 44 0 19 1 TS ^2 I ttyp0 0:00.03 sh 569 root 0.0 44 44 0 19 1 TS ^2 S ttyp0 0:00.31 csh 579 root 0.0 44 44 0 19 ~1 TS ^2 S + ttyp0 0:00.03 runon 580 root 0.0 44 44 0 19 ~1 TS ^2 S + ttyp0 0:00.03 sh 581 root 0.0 44 44 0 19 ~1 TS ^2 R + ttyp0 0:00.06 ls -l The display shows that all processes are running under the default timershare scheduling policy. Processes 458 and 561 are running unbound to processor 0 in processor set 0. Processes 567, 568, and 569, are running on processor 1 and are bound exclusively (^) to processor set 2. Processes 579, 580, and 581 are running bound to processor 1 (~) and are bound exclusively to processor set 2 (^). To display the name of the shell you are currently running, enter: ps -p $$ ENVIRONMENT VARIABLES
The following environment variables affect the execution of ps: Overrides the horizontal screen size, used to determine the number of text columns to display. Provides a default value for the internationalization variables that are unset or null. If LANG is unset or null, the corresponding value from the default locale is used. If any of the internationalization variables contain an invalid setting, the utility behaves as if none of the variables had been defined. If set to a non-empty string value, overrides the values of all the other interna- tionalization variables. Determines the locale for the interpretation of sequences of bytes of text data as characters (for example, sin- gle-byte as opposed to multibyte characters in arguments). Determines the locale for the format and contents of diagnostic messages writ- ten to standard error. Determines the format and contents of the date and time strings displayed. Determines the location of message cat- alogues for the processing of LC_MESSAGES. FILES
Searched to find terminal names. Process information. SEE ALSO
Commands: kill(1), nice(1), renice(8), runon(1), w(1) Functions: exec(2), exit(2), fork(2), getpriority(2), wait(2) Routines: nlist(3), sched_setscheduler(3) Files: processor_sets(4) Standards: standards(5) ps(1)

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