To debug a core file, type:
$ dbx program_name core
(dbx) debug -c core program_name
You can substitute - for the program name and dbx will attempt to extract the program name from the core file. dbx might not find the executable if its full path name is not available in the core file. If dbx does not find the executable, specify the complete path name of the binary when you tell dbx to load the core file.
If the core file is not in the current directory, you can specify its path name (for example, /tmp/core).
Use the where command (see where Command) to determine where the program was executing when it dumped core.
When you debug a core file, you can also evaluate variables and expressions to see the values they had at the time the program crashed, but you cannot evaluate expressions that make function calls. You cannot single step or set breakpoints.