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GCORE(1)                FreeBSD General Commands Manual               GCORE(1)

     gcore - get core images of running process

     gcore [-f] [-s] [-c core] [executable] pid

     The gcore utility creates a core image of the specified process, suitable
     for use with gdb(1).  By default, the core is written to the file
     ``core._pid_''.  The process identifier, pid, must be given on the
     command line.

     The following options are available:

     -c      Write the core file to the specified file instead of

     -f      Dumps all available segments, excluding only malformed and
             undumpable segments.  Unlike the default invocation, this flag
             dumps mappings of devices which may invalidate the state of
             device transactions or trigger other unexpected behavior.  As a
             result, this flag should only be used when the behavior of the
             application and any devices it has mapped is fully understood and
             any side effects can be controlled or tolerated.

     -s      Stop the process while gathering the core image, and resume it
             when done.  This guarantees that the resulting core dump will be
             in a consistent state.  The process is resumed even if it was
             already stopped.  The same effect can be achieved manually with

     core._pid_         the core image

     A gcore utility appeared in 4.2BSD.

     Because of the ptrace(2) usage gcore may not work with processes which
     are actively being investigated with truss(1) or gdb(1).  Additionally,
     interruptable sleeps may exit with EINTR.

     The gcore utility is not compatible with the original 4.2BSD version.

FreeBSD 11.0-PRERELEASE          July 14, 2010         FreeBSD 11.0-PRERELEASE


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