savecore(8) [bsd man page]

SAVECORE(8)						      System Manager's Manual						       SAVECORE(8)

NAME

       savecore - save a core dump of the operating system

SYNOPSIS

       savecore dirname [ system ]

DESCRIPTION

       Savecore  is  meant to be called at the end of the /etc/rc file.  Its function is to save the core dump of the system (if one was made) and
       to write a reboot message in the shutdown log.

       It saves the core image in the file dirname/core.n and its corresponding namelist in dirname/unix.n.  The second argument is  the  namelist
       for the system which made the core image; the current system is always assumed to be /unix.  The trailing ".n" in the pathnames is replaced
       by a number which grows every time savecore is run in that directory.

       Before savecore writes out a core image, it reads a number from the file dirname/minfree.  If there are fewer free blocks on the file  sys-
       tem  which contains dirname than the number obtained from the minfree file, the core dump is not done.  If the minfree file does not exist,
       savecore always writes out the core file (assuming that a core dump was taken).

       Savecore also writes a reboot message in the shut down log.  If the system crashed as a result of  a  panic,  savecore  records	the  panic
       string in the shut down log too.

       If  savecore detects that the system time is wrong because of a crash (the time in the core image is after the current time), it will reset
       the system time to its best estimate of the time, which is the time in the core image plus the elapsed time since the reboot.  It announces
       the time that it set when this occurs.

FILES

       /usr/adm/shutdownlogshutdown log
       /unix		   current UNIX

BUGS

       The method used to determine whether a dump is present, and to prevent the same core image from being saved multiple times, is not elegant.
       This information should be passed to init by the system; however, this is difficult because the system may have to  be  rebooted  a  second
       time if the root filesystem is patched.

3rd Berkeley Distribution													       SAVECORE(8)

SAVECORE(8)						    BSD System Manager's Manual 					       SAVECORE(8)

NAME

     savecore -- save a core dump of the operating system

SYNOPSIS

     savecore -c [-v] [device ...]
     savecore -C [-v] [device ...]
     savecore [-fkvz] [-m maxdumps] [directory [device ...]]

DESCRIPTION

     The savecore utility copies a core dump into directory, or the current working directory if no directory argument is given, and enters a
     reboot message and information about the core dump into the system log.

     The options are as follows:

     -C 	  Check to see if a dump exists, and display a brief message to indicate the status.  An exit status of 0 indicates that a dump is
		  there, 1 indicates that none exists.	This option is compatible only with the [-v] option.

     -c 	  Clear the dump, so that future invocations of savecore will ignore it.

     -f 	  Force a dump to be taken even if either the dump was cleared or if the dump header information is inconsistent.

     -k 	  Do not clear the dump after saving it.

     -m maxdumps  Maximum number of dumps to store.  Once the number of stored dumps is equal to maxdumps the counter will restart from 0.

     -v 	  Print out some additional debugging information.  Specify twice for more information.

     -z 	  Compress the core dump and kernel (see gzip(1)).

     The savecore utility looks for dumps on each device specified by the device argument(s), or on each device in /etc/fstab marked as ``dump''
     or ``swap''.  The savecore utility checks the core dump in various ways to make sure that it is complete.	If it passes these checks, it
     saves the core image in directory/vmcore.# and information about the core in directory/info.#.  For kernel textdumps generated with the
     textdump(4) facility, output will be stored in the tar(5) format and named directory/textdump.tar.#.  The ``#'' is the number from the first
     line of the file directory/bounds, and it is incremented and stored back into the file each time savecore successfully runs.

     The savecore utility also checks the available disk space before attempting to make the copies.  If there is insufficient disk space in the
     file system containing directory, or if the file directory/minfree exists and the number of free kilobytes (for non-superusers) in the file
     system after the copies were made would be less than the number in the first line of this file, the copies are not attempted.

     If savecore successfully copies the kernel and the core dump, the core dump is cleared so that future invocations of savecore will ignore it.

     The savecore utility is meant to be called near the end of the initialization file /etc/rc (see rc(8)).

SEE ALSO

     gzip(1), getbootfile(3), textdump(4), tar(5), dumpon(8), syslogd(8)

HISTORY

     The savecore utility appeared in 4.1BSD.

     Support for kernel textdumps appeared in FreeBSD 7.1.

BUGS

     The minfree code does not consider the effect of compression or sparse files.

BSD
								 December 17, 2012							       BSD