From mboxrd@z Thu Jan  1 00:00:00 1970
From: korfuri@gmail.com
Subject: Re : How to call another separate program and passing some variables in C?
Date: Tue, 14 Oct 2008 13:12:29 +0200
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References: <DF93814AEDB44B7484B8BF8F416AA50D@johnny>
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To: johnny_xing <johnny_xing@banshing.com>
Cc: linux-c-programming@vger.kernel.org

2008/10/14, johnny_xing <johnny_xing@banshing.com>:
> Hi,
>
> Forgive me if my question is so simple as I am a newbie to programming..
>
> I have two C programming and I want to call second C file within my first C
> program, upon calling, I need to pass some variables (like 1 or 0) to the
> second program.
>
> Can anyone tell me how to do? I searched system() but it seems not be able
> to do this.
>
> Thanks & Best Regards,
>
> Johnny
>
>
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Hi,

You can use system() if you build the command-line (e.g. with
sprintf()) to pass the arguments you want. Then you can access it in
your 2nd program with argc/argv.

An alternative is to use fork() and execve(). Please note that you
have to convert each argument to a string so execve() can use it. Here
again you can use sprintf() for this purpose.

But are you sure you need two separate programs ? You can build 2 C
files together into one binary. That makes passing variables much
easier as it results to a normal function call.

Hope this will help
Regards,
Uriel

-- 
Uriel "Korfuri" Corfa
Epitech student