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GCORE(1) FreeBSD General Commands Manual GCORE(1)
NAME
gcore - get core images of running process
SYNOPSIS
gcore [-f] [-k] [-c core] [executable] pid
DESCRIPTION
The gcore utility creates a core image of the specified process, suitable
for use with gdb(1) (ports/devel/gdb). 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
"core.<pid>".
-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.
-k Use the ptrace(2) PT_COREDUMP kernel facility to write the core
dump, instead of reading the process' memory and constructing the
dump file in gcore itself. This is faster, and the dump is
written by the same kernel code that writes core dumps upon fatal
signals.
FILES
core.<pid> the core image
HISTORY
A gcore utility appeared in 4.2BSD.
BUGS
Because of the ptrace(2) usage gcore may not work with processes which
are actively being investigated with truss(1) or gdb(1)
(ports/devel/gdb). Additionally, interruptable sleeps may exit with
EINTR.
The gcore utility is not compatible with the original 4.2BSD version.
FreeBSD 14.0-RELEASE-p11 April 24, 2021 FreeBSD 14.0-RELEASE-p11