Re: File conflict when using sigma in several instances of GP

[Bill Allombert <Bill.Allombert@math.u-bordeaux.fr>]

On Sat, Jun 18, 2016 at 09:58:59AM +0200, Lars Blomberg wrote:
> Hello,
> 
> Under  Windows10  I start  4 instances of GP 2.6.1 (32 bit) and run the same
> script (using sigma) in them.
> 
> They  runs ok for a while but then some instances fails with messages like
> 
>   *** sigma: error opening output file [rename]:
> `C:\Users\Lars\AppData\Local\Temp\MPfb/FREL'.
> 
>   *** sigma: error opening output file [rename]:
> `C:\Users\Lars\AppData\Local\Temp\MPfj/FREL'.
> 
> There are a multitude of folders named MPxx, where x is a small letter.

Hello Lars,

This is a known problem on Windows. For some reason the code dedicated
to clean up the temporary directories does not work as intended.
We do not know why.

What is the content of C:\Users\Lars\AppData\Local\Temp\MPfb ?

You probably have exhausted all 676 directories MPaa to MPzz.

> What are these files used for?

This file are used for the MPQS algorithm. This is an historical accident
(when the code was written, computers did not have enough RAM to do the
computation fully in memory).

> Can I direct the files each to its own folder so as to avoid the conflict?

This is already done, though you can set the environment variable TEMP
to different values.

Cheers,
Bill.