Thread: strncmp()

im tring to understand that command...
what is it comparing.. what if i was going to use
something like.. a letter instead of a number..
i tried a letter but it just keeps on looping... .. but im tring to understand what the command really does or is...

Code:

int main()
{

  char n, x;
  char str1[] = "testing partion comparing";
  char str2[] = "Testing other comparing";

  puts(str1);
  puts(str2);

  while(1)
  {
     puts("Enter number of characters to comare, 0 to exit\n");
     scanf("%d",&n);

     if(n <= 0)
         break;

     x = strncmp(str1, str2, n);
     printf("Comparing %d characters, strncmp() returns %d.\n\n\n",n, x);
  }
    return 0;
}

It will always fail (ie: not = 0) on the first character, because the fist letter is different. For a better test, try these strings instead:

"abcdeFg"
"abcdefg"

First use n as 5 characters. Then use it as 6.

That'll tell help. strncmp tells if one string comes before another by comparing each characters decimal value, character by character.

Quzah.

Also:
> char n, x;

These should be declared as int's:
int n, x;

I guess technically, n should be declared as size_t:

size_t n;
int x;