Thread: A simple question about Core Dump

Suppose you run a program called prog, it crashed and you got core.1234 file.

My questions are:
1) To me a core dump is nothing more than a series of records: where you made the function calls, what is the memory address, etc. So core.1234 is supposed to be a document rather than a binary file. It should be viewed by "less" or similar editor. But what I can see are garbage characters. Then what exactly is core dump?!

2) I know 2 ways to use gdb:
gdb prog
(gdb) run
...
(gdb) bt

OR

gdb prog core.1234
(gdb) bt

What are the differences ?

Originally Posted by meili100

1) To me a core dump is nothing more than a series of records:

Then you are wrong.

where you made the function calls, what is the memory address, etc.

Nothing of the sort.

Then what exactly is core dump?!

A precise image of the memory of the process along with some data concerning its registers and other system resources.

2) I know 2 ways to use gdb:
gdb prog
(gdb) run
...
(gdb) bt

OR

gdb prog core.1234
(gdb) bt

What are the differences ?

The second occurs after the fact.