what exactly does strcmp() do?

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  1. #1
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    what exactly does strcmp() do?

    Code:
    int strcmp ( const char *s1, const char *s2 );
    strcmp will accept two strings. It will return an integer. This integer will either be:

    Negative if s1 is less than s2.
    Zero if s1 and s2 are equal.
    Positive if s1 is greater than s2.
    What exactly is this checking? How is 'John' less, more than or equal to 'Joey'...I guess is my question.

  2. #2
    and the hat of wrongness Salem's Avatar
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    Lookup John and Joey in a dictionary.

    < is "John is before Joey" in the dictionary
    > is "John is after Joey" in the dictionary

    = 0 means that they are the same word.
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    Obviously, so it checks which comes first in the dictionary?

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    C++ Witch laserlight's Avatar
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    Not quite: it compares null terminated strings similiar to how you could use a dictionary to compare words.
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    Algorithm Dissector iMalc's Avatar
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    It performs a "lexicographical" comparison. Google that for more info
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    Quote Originally Posted by iMalc View Post
    It performs a "lexicographical" comparison. Google that for more info
    Perfect thanks.

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    Or use the man page.

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