[RFA/RFC] Add dump and load command to process record and replay

[Michael Snyder]

Eli Zaretskii wrote:
>> From: Hui Zhu <teawater@gmail.com>
>> Date: Sun, 30 Aug 2009 02:05:37 +0800
>> Cc: msnyder@vmware.com, gdb-patches@sourceware.org
>>
>>> "A core file"? you didn't really mean that, did you?
>> Yes, it really dump record log to a core file.  Now, record log is
>> together with core file.
> 
> Sorry, I don't understand: why would we want to have the record log in
> a core file?  What am I missing here?

Because the record-log itself does not record starting state --
only changes of state.  It is useless by itself if you don't
restore the starting state first.

Hui's original patch used the "gcore" command to save the
starting state, and "target core" to restore it.

The problem that I found with that was that it created two
independent files, core file and record-log file, and that
there was no way to assure ourselves (or the user) that the
two files corresponded to one another when they were re-loaded.

That's why I suggested combining them into one file --
in this implementation, by adding the record-log to an
extra section in the core file.