CHECKPROC(8) The SuSE boot concept CHECKPROC(8)NAME
Checkproc - Checks for a process by full path name
Pidofproc - Checks for a process by exec base name
SYNOPSIScheckproc [-vLkNz] [-x] [-p pid_file] [-i ingnore_file] [-c root]
/full/path/to/executable
checkproc-n [-vk] name_of_kernel_thread
checkproc [-vk] [-x] basename_of_executable
pidofproc [-LkNz] [-x] [-p pid_file] [-i ingnore_file] [-c root]
/full/path/to/executable
pidofproc -n [-k] name_of_kernel_thread
pidofproc [-k] [-x] basename_of_executable
SYNOPSIS LSB 3.1
pidofproc [-p pid_file] /full/path/to/executable
DESCRIPTIONcheckproc checks for running processes that use the specified exe‐
cutable.
checkproc does not use the pid to verify a process but the full path of
the corresponding program which is used to identify the executable (see
proc(5)). Only if the inode number (/proc/<pid>/exe) and the full name
are unavailable (/proc/<pid>/cmdline) or if the executable changes its
zeroth argument, checkproc uses the base name (/proc/<pid>/stat) to
identify the running program. Note that if the option -n for kernel
thread is given only (/proc/<pid>/stat) is used. For this case a
existing symbolic link (/proc/<pid>/exe) indicates that the <pid> is
not a kernel thread.
Extended functionality is provided by the -p pid_file option (former
option -f changed due to the LSB specification). If this option is
specified, checkproc tries to check the pid read from this file instead
of the default (/var/run/<basename>.pid). The pid read from this file
is compared against the pids of the processes that uses the specified
binary. If the option -k is specified, checkproc works like killproc
that is that if the if the pid_file does not exist, checkproc assumes
that the daemon is not running. It is possible to use a process iden‐
tity number instead of a pid file.
For the possibility of having two different sessions of one binary pro‐
gram, the option -i ignore_file allows to specify a pid file which pid
number is used to ignore all processes of corresponding process ses‐
sion.
Note that the behaviour above is changed by the option -k. With this
option, the pid read from the pid file is the only used pid (see kill‐
proc(8)) and with this option also exit codes like startproc(8) or
killproc(8) are used. Without this option, the pid read from the pid
file is used to search the process table for a process with an exe‐
cutable that matches the specified pathname. In order to avoid confu‐
sion with stale pid files, a not up-to-date pid will be ignored (see
startproc(8)).
The option -v makes checkproc print out verbose messages. The same
happens if pidofproc LSB variant is used. This version also accepts
also the base name only of a executable. Note that this disables the
comparision of the inodes of the executable and the information found
within the proc table (see proc(5)).
REQUIRED
/full/path/to/executable or name_of_kernel_thread
Specifies the executable which processes should be found, or
alternatively, if the option Or alternated, if option -n is
used, the name of the kernel thread. This argument is always
required.
OPTIONS-k This option makes checkproc work like killproc(8) which changes
the operation mode, e.g. the exit status of the program will be
that of killproc(8). Without this option, checkproc works like
startproc (8) and finds all processes with an executable that
matches the specified pathname, even if a given pid file (see
option -p) isn't up-to-date. Nevertheless it uses its own exit
status (see section EXIT CODES).
-L This option causes symlinks to be followed, as the like-named
option in ls(1). Note: for the file name the original name of
the program is used instead of the name of the symbolic link.
-p pid_file
Former option -f changed due to the LSB specification.) Use an
alternate pid file instead of the default /var/run/<base‐
name>.pid. If the option -k is specified and the pid_file does
not exist, checkproc assumes that the daemon is not running. It
is possible to use a process identity number instead of a pid
file.
-i ignore_file
The pid found in this file is used as session id of the same
binary program which should be ignored by checkproc.
-c root
Change root directory to root for services which have been
started with this option by startproc(8).
-n This option indicates that a kernel thread should be checked.
In this case not the executable with its full path name is
required but the name of the kernel thread.
-N With this option the location of the executable is checked about
NFS file system and if true the stat(2) system call is not
applied on the exe symbolic link under /proc(5). Otherwise
checkproc or pidofproc could be locked if the corresponding NFS
server is currently not online or available. This implies that
the inode number check between the exectuable on the command
line and the exectuable of the exec symbolic link will be
skipped.
-q This option is ignored.
-v Verbose output.
-z This option causes checkproc to see processes even if they are
in the zombie state. Without this option zombies are handled as
not existent because such a process isn't alive but listed in
the process table and waits on its parent process.
-x Tells checkproc as well as pidofproc to use the upto 15 byte
long filename name found in /proc/<pid>/stat to be able to iden‐
tify scripts overwriting their command line.
EXAMPLEcheckproc /usr/sbin/sendmail
returns all pids of running sendmail processes.
checkproc-p /var/myrun/lpd.pid /usr/sbin/lpd
returns the command line or the basename of the process pid
found in /var/run/lpd.pid.
EXIT CODES
The exit codes without the option -k have the following LSB conform
conditions:
0 Program is running
1 No process but pid file found
3 No process and no pid file found
4 Program is not installed
101 Wrong syntax on command line
102 Other errors
If the option -k is used checkproc uses exit codes like startproc(8) or
killproc(8) do:
0 Program is running
1 Generic or unspecified error
2 Invalid or excess argument(s)
4 Insufficient privilege(s)
5 Program is not installed
7 Program is not running
in some cases a message is send to standard error or, if no standard
error available, syslogd(8) is used.
NOTEcheckproc together with the option -v just like pidof(8). The only
difference is the usage of an available pid file. Only if no usable
pid is given with a pid file the process table will be scanned.
BUGS
Identifying a process based on the executable file and the correspond‐
ing inode number only works if the process stays alive during start‐
proc's execution. Processes rewriting their zeroth argument or shell
scripts (the inode number of the shell executable file is not identical
to that of the script file) may not be identified by a filename path.
FILES
/proc/ path to the proc file system (see proc(5)).
/etc/init.d/
path to the SuSE boot concept script base directory as required
by the Linux Standard Base Specification (LSB) (see
init.d(7)).
SEE ALSOstartproc(8), killproc(8), insserv(8), init.d(7), kill(1), skill(1),
killall(8), killall5(8), signal(7), proc(5).
COPYRIGHT
1994-2005 Werner Fink, 1996-2005 SuSE GmbH Nuernberg, Germany.
AUTHOR
Werner Fink <werner@suse.de>
3rd Berkeley Distribution Nov 10, 2000 CHECKPROC(8)
