Syntax

#include <string.h>  /* also in <memory.h> */
int memcmp(const void *buf1, const void *buf2, size_t count);

memcmp compares the first count bytes of buf1 and buf2.

memcmp returns a value indicating the relationship between the two buffers as follows: compact break=fit.

Value

Meaning
Less than 0
buf1 less than buf2
0
buf1 identical to buf2
Greater than 0
buf1 greater than buf2

This example compares first and second arguments passed to main to determine which, if either, is greater.

#include <stdio.h>#include <string.h>

int main(int argc,char **argv)
{
   int len;
   int result;

   if (argc != 3) {
      printf("Usage: %s string1 string2\n", argv[0]);
   }
   else {

      /* Determine the length to be used for comparison                       */

      if (strlen(argv[1]) < strlen(argv[2]))
         len = strlen(argv[1]);
      else
         len = strlen(argv[2]);
      result = memcmp(argv[1], argv[2], len);
      printf("When the first %i characters are compared,\n", len);
      if (0 == result)
         printf("\"%s\" is identical to \"%s\"\n", argv[1], argv[2]);
      else
         if (result < 0)

            printf("\"%s\" is less than \"%s\"\n", argv[1], argv[2]);
         else
            printf("\"%s\" is greater than \"%s\"\n", argv[1], argv[2]);
   }
   return 0;

   /****************************************************************************
      If the program is passed the arguments "firststring secondstring",
      the output should be:

      When the first 11 characters are compared,
      "firststring" is less than "secondstring"
   ****************************************************************************/
}

• memchr
  
• memcpy
  
• memicmp
  
• memmove
  
• memset
  
• strcmp

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