On Wed, 2 Mar 2005 21:22:55 +0000, Dave Mitchell <davem@[...].com>  wrote:
>  On Wed, Mar 02, 2005 at 09:52:46PM +0100, demerphq wrote:
>  > Ok, so if im not using mortals, but rather SAVEFREEPV it looks like
>  > the data is being stored on the save stack and not the tmpstack. So do
>  > i still need the SAVETMPS/FREETMPS? Can I not just use ENTER/LEAVE by
>  > itself?
>  
>  yes. Or possibly not even needing the ENTER/LEAVE. It all depends.
>  Since (a) I've still got a cold 

Sorry to hear that. :-(

>  (b) I havn't looked at your original patch and don't really feel up to it at the 
>  moment (see (a)), 

Fair enough. Its a big patch. 

> I don't have any idea of what tmp thing you're creating. 

Basically a short array of longs/void *

>  Is it during regex compilation or execution? 

Execution.

>  What purpose does it serve;  

It stores a set of information about where the char pointer was when a
given accepting state was entered. When more than one such point was
encountered its necessary to try (with a call to regmatch) to match
the rest of the regex after the tree at each point looking for a total
match. The array stores the state/positions remaining to be attempted.

>  how often is it created; 

Possibly often. Its hard to say. 

> what lifetime should it have during normal execution?

It should be freed as soon as the internal call to regmatch() completes.

>  
>  > I also wonder if there is a way I can save a variable somehow so its
>  > freed if the program dies, but otherwise is freed by myself. Is that
>  > possible somehow?
>  
>  Well, thatus what all the various ENTER/LEAVE, SAVETMPS type schemes do.
>  At the point in your code where you do LEAVE (or FREETMPS or whatever),
>  your SV will be freed. If your code dies before it gets to the line
>  containing the LEAVE, perl itself will do any necessary unwinding of the
>  savestack, ie it implicitly calls LEAVE on your behalf.

Ok, im going to meditate on all of this. Good luck with your cold.

Cheers,
Yves



-- 
First they ignore you, then they laugh at you, then they fight you,
then you win.
  +Gandhi