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From: korfuri@gmail.com
To: johnny_xing <johnny_xing@banshing.com>
Cc: linux-c-programming@vger.kernel.org
Subject: Re : How to call another separate program and passing some variables in C?
Date: Tue, 14 Oct 2008 13:12:29 +0200	[thread overview]
Message-ID: <c15440c50810140412r7df6c411xdf24dd6a16590132@mail.gmail.com> (raw)
In-Reply-To: <DF93814AEDB44B7484B8BF8F416AA50D@johnny>

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

  reply	other threads:[~2008-10-14 11:12 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-14 10:48 How to call another separate program and passing some variables in C? johnny_xing
2008-10-14 11:12 ` korfuri [this message]
2008-10-15  6:27   ` johnny_xing
     [not found]     ` <4f5c2ba10810142334o6dbca046r52eb267c8da28aa9@mail.gmail.com>
2008-10-15  8:31       ` johnny_xing
2008-10-15  9:05         ` Per Jessen
     [not found]       ` <5F844C5CE0B949348F25CDBF9B3FA11D@johnny>
     [not found]         ` <4f5c2ba10810150150k153b051fod1440a14037cd16c@mail.gmail.com>
     [not found]           ` <4f5c2ba10810150152s6c6307fi1fde09505b31a8bc@mail.gmail.com>
2008-10-15  9:10             ` johnny_xing
     [not found]               ` <4f5c2ba10810150227k44321974n4fe51ff28e470e2c@mail.gmail.com>
2008-10-15  9:35                 ` johnny_xing
2008-10-16  0:41               ` Jianjun Kong

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