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Date: Tue, 21 Feb 2006 16:45:40 +0100
From: Poul-Erik Andreasen <poulerik@pea.dk>
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Subject: Re: binding to C: popen
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Date: 2006-02-21T16:45:40+01:00
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jimmaureenrogers@worldnet.att.net wrote:
> Poul-Erik Andreasen wrote:
> 
>>This ictually going as it is suppose to, but i would like set in an
>>exception if the piping dosn't have succes. Acording to the C manual
>>popen returns null if it fails. But how do i test on that in the FILEs type?
> 
> 
> The popen man page describes the command as:
> FILE *popen(const char *command, const char *mode);
> 
> Note that popen returns a file pointer. Upon failure it returns a null
> pointer.
> 
> It seems that you might be able to test if the return value is null.
> 
> Jim Rogers
> 

Yes but a C pointer is in Ada represented as system.address and i can 
not test that for O the the systems.address_image gives 0804C060 and if 
that is a stadart c value for a null-pointer things are fine, but that 
seems to be a hack.


Poul-Erik