Saving the state of the program ?

Saving the state of the program ?

[Benoit de Boursetty]

Hi,

Does anyone know how to core-dump a running program, reboot, and then
restart the program from where it was ?

I suppose it is impossible when the program has, like, opened files or so,
but when it's just performing a computation with only stdin and stdout,
shouldn't it be possible ?

Thanks for your help
Benoît de Boursetty.

Re: Saving the state of the program ?

[Dave Mason]

>>>>> On Thu, 18 Nov 1999 23:28:24 +0100 (MET), Benoit de Boursetty <debourse@email.enst.fr> said:

> Hi, Does anyone know how to core-dump a running program, reboot, and
> then restart the program from where it was ?

Emacs does that.  Basically they do a core dump and then have a
(somewhat system dependent) unexec routine that turns the core file
into an executable.

The scm scheme system uses this, too.  That's probably the best place
to look.

../Dave

Re: Saving the state of the program ?

[Benoit de Boursetty]

On Fri, 19 Nov 1999, Dave Mason wrote:

> > Hi, Does anyone know how to core-dump a running program, reboot, and
> > then restart the program from where it was ?
>
> Emacs does that.  Basically they do a core dump and then have a
> (somewhat system dependent) unexec routine that turns the core file
> into an executable.
>
> The scm scheme system uses this, too.  That's probably the best place
> to look.

Thanks for the info. However, my question was about executables in the
general case...

Benoît de Boursetty

Re: Saving the state of the program ?

[Dave Mason]

>>>>> On Sun, 21 Nov 1999 14:47:56 +0100 (MET), Benoit de Boursetty <debourse@email.enst.fr> said:

> On Fri, 19 Nov 1999, Dave Mason wrote:
>> > Hi, Does anyone know how to core-dump a running program, reboot,
>> > and then restart the program from where it was ?
>> 
>> Emacs does that.  Basically they do a core dump and then have a
>> (somewhat system dependent) unexec routine that turns the core file
>> into an executable.
>> 
>> The scm scheme system uses this, too.  That's probably the best
>> place to look.

> Thanks for the info. However, my question was about executables in
> the general case...

That's what I was trying to point you to.  In scm you can say something like:
	(if (dump "new-executable")
	    (begin
		(display "\"new-executable\" successfully made\n")
		(exit 0)))
	...rest of the program...

It wouldn't be too hard to pull the code out of scm and add it to the
ocaml library.  But it would rewuire some C coding experience.

../Dave