memcmp, _fmemcmp

raw OCR

Compares two blocks for a length of exactly n bytes.

Defined in header <mem.h>

Syntax

#include <mem.h>
Near  version: int memcmp(const     void  *sl, const void *s2, sizet  n);
Far version: int far _fmemcmp(const     void  far *sl, const void far *s2,
                                  size_t n)

Portability

	DOS	UNIX	Windows	ANSI C	C++ only
Near version	■	■	■	■
Far version	■		■

Remarks

memcmp is available on UNIX System V systems.

memcmp compares the first n bytes of the blocks si and s2 as unsigned chars.

Return value

Because it compares bytes as unsigned chars, memcmp	returns a value

< 0 if si is less than s2 = 0 if si is the same as s2 > 0 if si is greater than s2

For example,

memcmp("\xFF", "\x7F", 1) returns a value greater than 0.

Example

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

int main(void)

   char *bufl = "aaa";
   char *buf2 = "bbb";
   char *buf3 = "ccc";
   int Stat;
   Stat = memcmp (buf2, bufl, strlen(buf2));
   if (Stat > 0)
      printf ("buffer 2 is greater than buffer l\n");
   else
      printf ("buffer 2 is less than buffer l\n");
   Stat = memcmp(buf2, buf3,  strlen(buf2));
   if (Stat > 0)
      printf("buffer 2 is greater  than buffer 3\n");
   else
      printf("buffer 2 is  less than buffer 3\n");
   return 0;

Differences from modern implementations

Nothing recorded yet.

Modern references

These are search links, not yet checked by hand.

Extraction notes

heading `memcmp, Jmemcmp` read as `memcmp, _fmemcmp`

Stable link: /3.1/mem.h/memcmp/ · short form /3.1/memcmp/