1.\" Copyright (c) 1983, 1990, 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)gcore.1 8.2 (Berkeley) 4/18/94 29.\" 30.Dd April 24, 2021 31.Dt GCORE 1 32.Os 33.Sh NAME 34.Nm gcore 35.Nd get core images of running process 36.Sh SYNOPSIS 37.Nm 38.Op Fl f 39.Op Fl k 40.Op Fl c Ar core 41.Op Ar executable 42.Ar pid 43.Sh DESCRIPTION 44The 45.Nm 46utility creates a core image of the specified process, 47suitable for use with 48.Xr gdb 1 Pq Pa ports/devel/gdb . 49By default, the core is written to the file 50.Dq Pa core.<pid> . 51The process identifier, 52.Ar pid , 53must be given on the command line. 54.Pp 55The following options are available: 56.Bl -tag -width indent 57.It Fl c 58Write the core file to the specified file instead of 59.Dq Pa core.<pid> . 60.It Fl f 61Dumps all available segments, excluding only malformed and undumpable 62segments. 63Unlike the default invocation, this flag dumps mappings of devices which 64may invalidate the state of device transactions or trigger other unexpected 65behavior. 66As a result, this flag should only be used when the behavior of the 67application and any devices it has mapped is fully understood and any side 68effects can be controlled or tolerated. 69.It Fl k 70Use the 71.Xr ptrace 2 72.Dv PT_COREDUMP 73kernel facility to write the core dump, instead of reading the process' 74memory and constructing the dump file in 75.Nm 76itself. 77This is faster, and the dump is written by the 78same kernel code that writes core dumps upon fatal signals. 79.El 80.Sh FILES 81.Bl -tag -width /var/log/messages -compact 82.It Pa core.<pid> 83the core image 84.El 85.Sh HISTORY 86A 87.Nm 88utility appeared in 89.Bx 4.2 . 90.Sh BUGS 91Because of the 92.Xr ptrace 2 93usage 94.Nm 95may not work with processes which are actively being investigated with 96.Xr truss 1 97or 98.Xr gdb 1 Pq Pa ports/devel/gdb . 99Additionally, interruptable sleeps may exit with EINTR. 100.Pp 101The 102.Nm 103utility is not compatible with the original 104.Bx 4.2 105version. 106