bsd/man/man5/core.5

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  15 .Dd June 26, 2008
  16 .Dt CORE 5
  17 .Os
  18 .Sh NAME
  19 .Nm core
  20 .Nd memory image file format
  21 .Sh SYNOPSIS
  22 .In sys/param.h
  23 .Sh DESCRIPTION
  24 A small number of signals which cause abnormal termination of a process
  25 also cause a record of the process's in-core state to be written
  26 to disk for later examination by one of the available debuggers.
  27 (See
  28 .Xr sigaction 2 . )
  29 This memory image is written to a file named by default
  30 .Pa core.pid ,
  31 where
  32 .Va pid
  33 is the process ID of the process,
  34 in the
  35 .Pa /cores
  36 directory,
  37 provided the terminated process had write permission in the directory,
  38 and the directory existed.
  39 .Pp
  40 The maximum size of a core file is limited by
  41 .Xr setrlimit 2 .
  42 Files which would be larger than the limit are not created.
  43 .Pp
  44 The core file consists of the
  45 .Xr Mach-O 5
  46 header as  described in the
  47 .Aq Pa mach-o/loader.h
  48 file.
  49 The remainder of the core
  50 file consists of various sections described in the
  51 .Xr Mach-O 5
  52 header.
  53 .Sh NOTE
  54 Core dumps are disabled by default under Darwin/Mac OS X.  To re-enable
  55 core dumps, a privileged user must do one of the following
  56 .Pp
  57 * Edit
  58 .Pa /etc/launchd.conf
  59 or
  60 .Pa $HOME/.launchd.conf
  61 and add a line specifying the limit
  62 .Pa limit core unlimited
  63 .Pp
  64 * A privileged user can also enable cores with
  65 .Pa launchctl limit core unlimited
  66 .Pp
  67 * A privileged user can also enable core files by using
  68 .Xr ulimit 1
  69 or
  70 .Xr limit 1
  71 depending upon the shell.
  72 .Sh SEE ALSO
  73 .Xr gdb 1 ,
  74 .Xr setrlimit 2 ,
  75 .Xr sigaction 2 ,
  76 .Xr Mach-O 5 ,
  77 .Xr launchd.conf 5 ,
  78 .Xr launchd.plist 5 ,
  79 .Xr sysctl 8
  80 .Sh HISTORY
  81 A
  82 .Nm
  83 file format appeared in
  84 .At v6 .