ps(1) (BSD Compatibility Package ) ps(1)
NAME
ps - display the status of current processes
SYNOPSIS
/usr/ucb/ps [ -acglnrSuUvwx ] [ -tterm ] [ num ]
DESCRIPTION
The ps command displays information about processes. Normally, only
those processes that are running with your effective user ID and are
attached to a controlling terminal (see termio(4)) are shown.
Additional categories of processes can be added to the display using
various options. In particular, the -a option allows you to include
processes that are not owned by you (that do not have your user ID),
and the -x option allows you to include processes without control
terminals. When you specify both -a and -x, you get processes owned
by anyone, with or without a control terminal. The -r option
restricts the list of processes printed to running and runnable
processes.
ps displays the process ID, under PID; the control terminal (if any),
under TT; the cpu time used by the process so far, including both
user and system time, under TIME; the state of the process, under S;
and finally, an indication of the COMMAND that is running.
The state is given by a single letter from the following:
O Process is running on a processor.
S Sleeping. Process is waiting for an event to
complete.
R Runnable. Process is on run queue.
I Idle. Process is being created.
Z Zombie state. Process terminated and parent not
waiting.
T Traced. Process stopped by a signal because
parent is tracing it.
X SXBRK state. Process is waiting for more
primary memory.
The following options must all be combined to form the first
argument:
-a Include information about processes owned by others.
-c Display the command name, as stored internally in the system
for purposes of accounting, rather than the command arguments,
which are kept in the process' address space. This is more
reliable, if less informative, since the process is free to
destroy the latter information.
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ps(1) (BSD Compatibility Package ) ps(1)
-g Display 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 login on free terminals.
-l Display a long listing, with fields F, PPID, CP, PRI, NI, SZ,
RSS and WCHAN as described below.
-n Produce numerical output for some fields. In a user listing,
the USER field is replaced by a UID field.
-r Restrict output to running and runnable processes.
-S Display accumulated CPU time used by this process and all of
its reaped children.
-u Display user-oriented output. This includes fields USER, SZ,
RSS and START as described below.
-U Update a private database where ps keeps system information.
-v Display a version of the output containing virtual memory.
This includes fields SIZE and RSS, described below.
-w Use a wide output format (132 columns rather than 80); if
repeated, that is, -ww, use arbitrarily wide output. This
information is used to decide how much of long commands to
print.
-x Include processes with no controlling terminal.
-tterm
List only process data associated with the terminal, term.
Terminal identifiers may be specified in one of two forms: the
device's file name (for example, tty04 or term/14) or, if the
device's file name starts with tty, just the digit identifier
(for example, 04).
num A process number may be given, in which case the output is
restricted to that process. This option must be supplied last.
DISPLAY FORMATS
Fields that are not common to all output formats:
USER Name of the owner of the process.
NI Process scheduling increment [see getpriority(3) and
nice(3C)].
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ps(1) (BSD Compatibility Package ) ps(1)
SIZE
SZ The combined size of the data and stack segments (in
kilobyte units)
RSS Real memory (resident set) size of the process (in
kilobyte units).
UID Numerical user-ID of process owner.
PPID Numerical ID of parent of process.
CP Short-term CPU utilization factor (used in scheduling).
PRI The priority of the process (higher numbers mean lower
priority).
START The starting time of the process, given in hours,
minutes, and seconds. A process begun more than 24 hours
before the ps inquiry is executed is given in months and
days.
WCHAN The address of an event for which the process is
sleeping, or in SXBRK state (if blank, the process is
running).
F Flags (hexadecimal and additive) associated with the
process:
00 Process has terminated. Process table
now available.
01 A system process, always in primary
memory.
02 Parent is tracing process.
04 Tracing parent's signal has stopped
process. Parent is waiting, see
ptrace(2).
08 Process is currently in primary memory.
10 Process currently in primary memory,
locked until an event is completed.
A process that has exited and has a parent, but has not yet been
waited for by the parent is marked <defunct>; otherwise, ps tries to
determine the command name and arguments given when the process was
created by examining the user block.
FILES
/dev
/dev/sxt/*
/dev/tty*
/dev/xt/* terminal (tty) names searcher files
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ps(1) (BSD Compatibility Package ) ps(1)
/dev/kmem kernel virtual memory
/dev/swap default swap device
/dev/mem memory
/etc/passwd UID information supplier
/etc/ps_data internal data structure
SEE ALSO
getpriority(3), nice(3C)
kill(1) in the User's Reference Manual.
lseek(2) in the Programmer's Reference Manual.
NOTES
Things can change while ps is running; the picture it gives is only a
close approximation to the current state. Some data printed for
defunct processes is irrelevant.
If no term or num is specified, ps checks the standard input, the
standard output, and the standard error in that order, looking for
the controlling terminal and will attempt to report on processes
associated with the controlling terminal. In this situation, if the
standard input, the standard output, and the standard error are all
redirected, ps will not find a controlling terminal, so there will be
no report.
On a heavily loaded system, ps may report an lseek(2) error and exit.
ps may seek to an invalid user area address, having obtained the
address of process' user area, ps may not be able to seek to that
address before the process exits and the address becomes invalid.
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