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From: Lynn McGuire <lynnmcguire5@gmail.com>
Newsgroups: comp.lang.fortran
Subject: Re: how do you send a fortran character string from GCC to GFortran ?
Date: Thu, 2 Jan 2025 14:45:36 -0600
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On 1/2/2025 4:06 AM, Thomas Koenig wrote:
> Lynn McGuire <lynnmcguire5@gmail.com> schrieb:
>> How do you send a fortran character string from GCC to GFortran ?
>>
>> I cannot get this to link.  I can do the reverse, send a fortran
>> character string from Gfortran to GCC.
> 
> A full, self-contained example would be helpful for somebody trying to
> help (especially since you say "link", which seems weird).
> 
> But take a look at
> 
> https://gcc.gnu.org/onlinedocs/gfortran/Naming-and-argument-passing-conventions.html
> 
>> I do have the additional complication that I do not know the length of
>> the fortran character string being sent from GCC to Gfortran at compile
>> time, only run time.  So that is a character*(*) string.
>>
>> I am not using the ISO C binding.
> 
> It is generally a good idea to use ISO C binding in new code, it
> is what it was introduced for.
> 
> But you might also find
> 
> https://gcc.gnu.org/onlinedocs/gfortran/Interoperability-Options.html
> 
> of interest.

Thanks !  When I was writing the reply to you, I figured out the 
problem.  I forgot to put 'extern "C"' in front of the function 
declaration for my fortran code.  That fixed my link.

It is the little things that get you.

Thanks,
Lynn