Thread: Creating a sysctl variable ?

  1. #1
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    Creating a sysctl variable ?

    Hi,

    I'd need to create a variable that keeps track of something happening in my function. So I don't want my variable to be initialized each time the function is called, I want it to stay.

    I guess I can create a sysctl variable for that purpose. How do I do that ?

    The thing is, the function is part of the linux TCP stack, and I don't know where the most global variable are declared. I'm a beginner in C programming & Linux.
    Last edited by taupin; 06-28-2008 at 05:02 PM.

  2. #2
    Deathray Engineer MacGyver's Avatar
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    I think perhaps you just want a local static variable in your function.

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    Okay, but where do I declare it ? I don't want it to be declared in a function where it'd intinialized several times. The function I'm talking about will be part of the Linux TCP stack. I'm a beginner in programming.

  4. #4
    Deathray Engineer MacGyver's Avatar
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    Quote Originally Posted by taupin View Post
    Okay, but where do I declare it ?
    Inside your function like I said.

    Quote Originally Posted by taupin View Post
    I don't want it to be declared in a function where it'd intinialized several times.
    Read up on static variables. They are akin in ways to global variables with limited scope. They are initialized once and then only altered as you change them.

    Quote Originally Posted by taupin View Post
    The function I'm talking about will be part of the Linux TCP stack. I'm a beginner in programming.
    Quite a paradox.

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    Alright, I didn't know about static variables. Thanks

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