Can someone please explain strings to me?

This is a discussion on Can someone please explain strings to me? within the C Programming forums, part of the General Programming Boards category; stupid question : if older compilers didnt add the /0 at the end of string for you but the ne ...

  1. #16
    Registered User
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    28
    stupid question : if older compilers didnt add the /0 at the end of string for you but the ne wones do what happens if in a new compiler you add the /0 will the compiler add another to the end of that or does it know ones already there?

  2. #17
    End Of Line Hammer's Avatar
    Join Date
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    Originally posted by lithium
    also never use:
    strcpy
    strcmp

    or functions similar to those. instead use:
    strncpy
    strncmp

    this will aviod buffer overflows (segmentation faults).
    @lithium: Please explain how you get a buffer overflow from using strcmp().

    For those that aren't aware, strncpy() isn't guaranteed to null terminate the array.
    Code:
    /*
     * The error here is that use programmer expected 
     * strncpy() to make s equal BBBB\0 or BBBBB\0.  
     * See the results below to see what actually happens.
     */
    
    #include <string.h>
    #include <stdio.h>
    
    int main(void)
    {
      char s[10] = "aaaaaaaa";
      puts(s);
      strncpy(s, "BBBBBBBB", 5);
      puts(s);
    }
    
    /* 
      Output:
      
      aaaaaaaa
      BBBBBaaa
      
      */
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  3. #18
    ... kermit's Avatar
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    1,528
    Originally posted by Thantos
    Considering that a good number of students are using a Borland compiler from the 1980s I'd say that there is a good chance.
    Ah, why should I have assumed that *everyone* would be using the latest version of gcc? (kidding, but yeah I was not thinking of that at all)

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