Command Section
SAVECORE(8)             FreeBSD System Manager's Manual            SAVECORE(8)

     savecore - save a core dump of the operating system

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

     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:

     --libxo            Generate output via libxo(3) in a selection of
                        different human and machine readable formats.  See
                        xo_parse_args(3) for details on command line

     -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]

     -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

     -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)).

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

     The savecore utility appeared in 4.1BSD.

     Support for kernel textdumps appeared in FreeBSD 7.1.

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

FreeBSD 11.1-RELEASE-p4        December 1, 2015        FreeBSD 11.1-RELEASE-p4
Command Section