Debugging, a core business

When a program crashes, it will create a core dump. A core dump is a memory image of the code and data of the program when it crashes. This core dump can be used by a debugger to locate the offending instruction without having to run the program within the debugger. Make sure that core dumps really get created; it is possible to limit the coredumpsize to 0, thereby disabling core dumps.

When the faulty program of the previous section is run, it will crash and create a core dump:

$$ bug
5
Memory fault - core dumped
 ls -al core
-rw-r--r--   1 se       prac       63276 Aug 13 10:42 core
$$

 gdb bug core
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GDB 4.15.1 (sparc-sun-solaris2.4), 
Copyright 1995 Free Software Foundation, Inc...
Core was generated by `bug'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /usr/lib/libc.so.1...done.
Reading symbols from /usr/lib/libdl.so.1...done.
#0  0x106b4 in printptr (iptr=0x0) at bug.c:8
8           printf("%d\n", *iptr);
(gdb)