PS(1) UNIX Programmer's Manual PS(1) NAME ps - process status SYNOPSIS ps [ acgklnrtuwxU# [ core [ swap [ system ] ] ] ] DESCRIPTION _P_s prints certain indicia about active processes. To get a complete printout on the console or lpr, use ``ps axlw'' For a quick snapshot of system activity, ``ps au'' is recom- mended. A hyphen may precede options with no effect. The following options may be specified. a asks for information about all processes with terminals (ordinarily only one's own processes are displayed). c causes only the _c_o_m_m field to be displayed instead of the arguments. (The comm field is the tail of the path name of the file the process last exec'ed.) This option speeds up _p_s somewhat and reduces the amount of output. It is also more reliable since the process can't scrib- ble on top of it. g asks for all processes. Without this option, _p_s only prints ``interesting'' processes. Processes are deemed to be uninteresting if they are process group leaders, or if their arguments begin with a `-'. This normally eliminates shells and getty processes. k causes the file /_u_s_r/_s_y_s/_c_o_r_e is used in place of /_d_e_v/_k_m_e_m and /_d_e_v/_m_e_m. This is used for postmortem system debugging. l asks for a long listing. The short listing contains the user name, process ID, tty, the cumulative execu- tion time of the process and an approximation to the command line. n asks for numeric rather than symbolic wchans. This flag implies the ``l'' flag. r asks for ``raw'' output. A non-human readable sequence of structures is output on the standard output. There is one structure for each process, the format is defined by t_t_t_y_n_a_m_e restricts output to processes whose controlling tty is the specified ttyname (which should be specified as printed by _p_s, including _t? for processes with no tty). This option must be the last one given. Printed 11/26/99 1 PS(1) UNIX Programmer's Manual PS(1) u A user oriented output is produced. This includes the name of the owner of the process, process id, nice value, size, tty, cpu time used, and the command. w tells _p_s you are on a wide terminal (132 columns). _P_s normally assumes you are on an 80 column terminal. This information is used to decide how much of long commands to print. The w option may be repeated, e.g. ww, and the entire command, up to 128 characters, will be printed without regard to terminal width. x asks even about processes with no terminal. U causes ps to update a private database where is keeps system information. Thus ``ps -U'' should be included in the /etc/rc file. # A process number may be given, (indicated here by #), in which case the output is restricted to that process. This option must also be last. A second argument tells _p_s where to look for _c_o_r_e if the _k option is given, instead of /usr/sys/core. A third argument is the name of a swap file to use instead of the default /dev/swap. If a fourth argument is given, it is taken to be the file containing the system's namelist. Otherwise, ``/unix'' is used. The output is sorted by tty, then by process ID. The long listing is columnar and contains F Flags associated with the process. These are defined by #define lines in /usr/include/sys/proc.h. S The state of the process. 0: nonexistent; S: sleeping; W: waiting; R: running; I: intermediate; Z: terminated; T: stopped. UID The user id of the process owner. PID The process ID of the process; as in certain cults it is possible to kill a process if you know its true name. PPID The process ID of the parent process. CPU Processor utilization for scheduling. PRI The priority of the process; high numbers mean low priority. Printed 11/26/99 2 PS(1) UNIX Programmer's Manual PS(1) NICE Used in priority computation. ADDR The memory address of the process if resident, other- wise the disk address. SZ The size in blocks (512 bytes) of the memory image of the process. WCHAN The event for which the process is waiting or sleeping; if blank, the process is running. TTY The controlling tty for the process. TIME The cumulative execution time for the process. COMMAND The command and its arguments. A process that has exited and has a parent, but has not yet been waited for by the parent is marked . _P_s makes an educated guess as to the file name and arguments given when the process was created by examining memory or the swap area. The method is inherently somewhat unreliable and in any event a process is entitled to destroy this information, so the names cannot be counted on too much. FILES /unix system namelist /dev/kmem kernel memory /dev/swap swap device /usr/sys/core core file /dev searched to find swap device and tty names /var/run/psdatabase system namelist and device information SEE ALSO kill(1), w(1), pstat(8) BUGS Things can change while _p_s is running; the picture it gives is only a close approximation to reality. Some processes, typically those in the background, are printed with null or garbaged arguments, even though the process has not swapped. (Sometimes ps even loses on its own arguments!) In these cases, the name of the command is printed in parentheses. When automatic crash dumps are enabled, /usr/sys/core is not a sensible default core file name. Printed 11/26/99 3