auto?

This is a discussion on auto? within the C Programming forums, part of the General Programming Boards category; What the hell does auto do? Yep, I didn't search google, I want the info direct from a C guru ...

  1. #1
    Supermassive black hole cboard_member's Avatar
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    auto?

    What the hell does auto do? Yep, I didn't search google, I want the info direct from a C guru who might be loitering

    I was happily going to use auto as an identifier then my trusty IDE highlighted it. I've never seen it used anywhere before.
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  2. #2
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    It's the default keyword used for variables. The counterpart to static. If you have:
    Code:
    int num;
    it's the same as having:
    Code:
    auto int num;
    Your IDE should also be able to tell you that.

    EDIT: Regarding its usefulness see: http://www.eskimo.com/~scs/C-faq/q1.12.html
    Last edited by itsme86; 10-06-2005 at 01:05 PM.
    If you understand what you're doing, you're not learning anything.

  3. #3
    Supermassive black hole cboard_member's Avatar
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    Quote Originally Posted by itsme86
    It's the default keyword used for variables. The counterpart to static. If you have:
    Code:
    int num;
    it's the same as having:
    Code:
    auto int num;
    Your IDE should also be able to tell you that.

    EDIT: Regarding its usefulness see: http://www.eskimo.com/~scs/C-faq/q1.12.html
    Hmm. Can we expect to see it removed from the language in the future?
    Good class architecture is not like a Swiss Army Knife; it should be more like a well balanced throwing knife.

    - Mike McShaffry

  4. #4
    ATH0 quzah's Avatar
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    Quote Originally Posted by ahluka
    Hmm. Can we expect to see it removed from the language in the future?
    No. They like to keep things for backwards compatability. Feel free to refer to this post in the future and say I'm wrong, but I won't hold my breath. Want proof? gets


    Quzah.
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    Registered User TactX's Avatar
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    Quote Originally Posted by quzah
    Want proof? gets
    Good point

    But well, I know people that want strcpy() to be removed because strncpy() is sooooo much safer

  6. #6
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    Yeah, but strcpy() is only unsafe when used on an untrusted source string. gets() is never safe.

    Okay, I guess there's the extremely rare circumstance such as head -c 50 some_file | my_program_that_uses_gets_with_a_buffer_bigger_tha n_50 but come on...

    strcpy() is perfectly safe as long as you know what you're doing with it.
    If you understand what you're doing, you're not learning anything.

  7. #7
    Registered User TactX's Avatar
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    You do get irony, do you?

  8. #8
    cwr
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    Actually the auto keyword is good for declaring vehicles:

    See question 1.8 of http://www.plethora.net/~seebs/faqs/...html#section-1


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    One word: LOL

  10. #10
    and the hat of wrongness Salem's Avatar
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    > because strncpy() is sooooo much safer
    True, but the disaster normally strikes on the next line when you realise that strncpy() doesn't always copy the \0 at the end of the string, so something which expects to find a \0 is out of luck.
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