Files and Tasking

Files and Tasking

[Emmanuel CHIVA]

Hello,

We found a limitation when using the gcc compiler with an Ada95 program:

it seems that the number of files that can simultaneously be opened by concurrent
tasks is limited to 60! Has anybody observed such a problem? And if so, how
to override this limitation?

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Re: Files and Tasking

[Theodore E. Dennison]

Emmanuel CHIVA wrote:
> 
> We found a limitation when using the gcc compiler with an Ada95 program:
> 
> it seems that the number of files that can simultaneously be opened by concurrent
> tasks is limited to 60! Has anybody observed such a problem? And if so, how
> to override this limitation?

What platform are you using? 

Most OS's have a limit on the number of files that any one process may have 
open at one time. I suspect it is this limit, not a gcc limit, that you
are running into.


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T.E.D.          
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Re: Files and Tasking

[Samuel Tardieu]

>>>>> "Emmanuel" == Emmanuel CHIVA <chiva@ens.fr> writes:

Emmanuel> Hello, We found a limitation when using the gcc compiler
Emmanuel> with an Ada95 program:

Emmanuel> it seems that the number of files that can simultaneously be
Emmanuel> opened by concurrent tasks is limited to 60! Has anybody
Emmanuel> observed such a problem? And if so, how to override this
Emmanuel> limitation?

Try typing "man `basename $SHELL`" and look at the "limit" command. I
doubt that GNAT (the name of the Ada compiler integrated within gcc)
limits the number of file descriptors.

  Sam

PS/ the "man ..." command will work on Un*x boxes only, I cannot help
    you if you're using the DOS version of GNAT.
-- 
"La cervelle des petits enfants, ca doit avoir comme un petit gout de noisette"
                                                       Charles Baudelaire

Re: Files and Tasking

[Michael Feldman]

In article <qw64tmqw322.fsf@gargantua.enst.fr>,
Samuel Tardieu  <sam@inf.enst.fr> wrote:
>
>PS/ the "man ..." command will work on Un*x boxes only, I cannot help
>    you if you're using the DOS version of GNAT.

I can. The maximum number of open files in DOS is determined by
the line FILES=kkk in your CONFIG.SYS file. If there is no such line
there, add one, and fill in your favorite value for kkk. Note that each
file handle takes up RAM, so there is no free lunch. 

In any case, GNAT is unlikely to impose a limit; these things are
typically handled by the OS.

Mike Feldman