core(5) [freebsd man page]

CORE(5) 						      BSD File Formats Manual							   CORE(5)

NAME

     core -- memory image file format

SYNOPSIS

     #include <sys/param.h>

DESCRIPTION

     A small number of signals which cause abnormal termination of a process also cause a record of the process's in-core state to be written to
     disk for later examination by one of the available debuggers.  (See sigaction(2).)  This memory image is written to a file named by default
     programname.core in the working directory; provided the terminated process had write permission in the directory, and provided the abnormal-
     ity did not cause a system crash.	(In this event, the decision to save the core file is arbitrary, see savecore(8).)

     The maximum size of a core file is limited by setrlimit(2).  Files which would be larger than the limit are not created.

     The name of the file is controlled via the sysctl(8) variable kern.corefile.  The contents of this variable describes a filename to store the
     core image to.  This filename can be absolute, or relative (which will resolve to the current working directory of the program generating
     it).

     The following format specifiers may be used in the kern.corefile sysctl to insert additional information into the resulting core file name:
	  %H	      Machine hostname.
	  %I	      An index starting at zero until the sysctl debug.ncores is reached.  This can be useful for limiting the number of corefiles
		      generated by a particular process.
	  %N	      process name.
	  %P	      processes PID.
	  %U	      process UID.

     The name defaults to %N.core, yielding the traditional FreeBSD behaviour.

     By default, a process that changes user or group credentials whether real or effective will not create a corefile.  This behaviour can be
     changed to generate a core dump by setting the sysctl(8) variable kern.sugid_coredump to 1.

     Corefiles can be compressed by the kernel if the following items are included in the kernel configuration file:
	  options     COMPRESS_USER_CORES
	  devices     gzio

     When COMPRESS_USER_CORES is included the following sysctls can control if core files will be compressed:
	  kern.compress_user_cores_gzlevel  Gzip compression level.  Defaults to -1.
	  kern.compress_user_cores	    Actually compress user cores.  Core files will have the suffix .gz appended to them.

EXAMPLES

     In order to store all core images in per-user private areas under /var/coredumps, the following sysctl(8) command can be used:

	   sysctl kern.corefile=/var/coredumps/%U/%N.core

SEE ALSO

     gdb(1), kgdb(1), setrlimit(2), sigaction(2), sysctl(8)

HISTORY

     A core file format appeared in Version 6 AT&T UNIX.

BSD
								 November 22, 2012							       BSD

gcore(1)                                                           User Commands                                                          gcore(1)

NAME

       gcore - get core images of running processes

SYNOPSIS

       gcore [-pgF] [-o filename] [-c content] process-id...

DESCRIPTION

       The gcore utility creates a core image of each specified process. By default, the name of the core image file for the process whose process
       ID is process-id will be core.process-id.

OPTIONS

       The following options are supported:

       -c content      Produces core image files with the specified content. The content description uses the same tokens as in  coreadm(1M).  The
                       -c option does not apply to cores produced due to the -p or -g flags.

       -F              Force. Grabs the target process even if  another  process has control.

       -g              Produces core image files in the global core file repository with the global content as configured by coreadm(1M). The com-
                       mand will fail if the user does not have permissions to the global core file repository.

       -o filename     Substitutes filename in place of core as the first part of the name of the core image files. filename can contain the  same
                       tokens to be expanded as the paths in coreadm(1M).

       -p              Produces  a  core image file in the process-specific location with the process-specific content for each process as config-
                       ured by coreadm(1M). The command will fail if the user does not have permissions to the per-process core file repository.

OPERANDS

       The following operand is supported:

       process-id      process ID

EXIT STATUS

       The following exit values are returned:

       0               On success.

       non-zero        On failure, such as non-existent process ID.

FILES

       core.process-id         core images

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Availability                 |SUNWtoo                      |
       +-----------------------------+-----------------------------+
       |Interface Stability          |See below.                   |
       +-----------------------------+-----------------------------+

       Command Syntax is Evolving. Output Format(s) are Unstable.

SEE ALSO

       kill(1), coreadm(1M), setrlimit(2), core(4), proc(4), attributes(5)

NOTES

       gcore is unaffected by the setrlimit(2) system call using the RLIMIT_CORE value.

SunOS 5.10                                                          11 Feb 2004                                                           gcore(1)