NAME¶
savecore —
save a core dump of the
operating system
SYNOPSIS¶
savecore |
-C [-v]
[directory device] |
savecore |
[-fkvz]
[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.
- -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.