memory(3C) — Interactive 2.2



          MEMORY(3C)           INTERACTIVE UNIX System           MEMORY(3C)



          NAME
               memory: memccpy, memchr, memcmp, memcpy, memset - memory
               operations

          SYNOPSIS
               #include <memory.h>

               char *memccpy (s1, s2, c, n)
               char *s1, *s2;
               int c, n;

               char *memchr (s, c, n)
               char *s;
               int c, n;

               int memcmp (s1, s2, n)
               char *s1, *s2;
               int n;

               char *memcpy (s1, s2, n)
               char *s1, *s2;
               int n;

               char *memset (s, c, n)
               char *s;
               int c, n;

          DESCRIPTION
               These functions operate as efficiently as possible on memory
               areas (arrays of characters bounded by a count, not ter-
               minated by a null character).  They do not check for the
               overflow of any receiving memory area.

               Memccpy copies characters from memory area s2 into s1, stop-
               ping after the first occurrence of character c has been
               copied, or after n characters have been copied, whichever
               comes first.  It returns a pointer to the character after
               the copy of c in s1, or a NULL pointer if c was not found in
               the first n characters of s2.

               Memchr returns a pointer to the first occurrence of charac-
               ter c in the first n characters of memory area s, or a NULL
               pointer if c does not occur.

               Memcmp compares its arguments, looking at the first n char-
               acters only, and returns an integer less than, equal to, or
               greater than 0, according as s1 is lexicographically less
               than, equal to, or greater than s2.

               Memcpy copies n characters from memory area s2 to s1.  It
               returns s1.

               Memset sets the first n characters in memory area s to the


          Rev. C Software Development Set                            Page 1



          MEMORY(3C)           INTERACTIVE UNIX System           MEMORY(3C)



               value of character c.  It returns s.

               For user convenience, all these functions are declared in
               the optional <memory.h> header file.



















































          Rev. C Software Development Set                            Page 2



          MEMORY(3C)           INTERACTIVE UNIX System           MEMORY(3C)



          CAVEATS
               Memcmp is implemented by using the most natural character
               comparison on the machine.  Thus the sign of the value
               returned when one of the characters has its high order bit
               set is not the same in all implementations and should not be
               relied upon.

               Character movement is performed differently in different
               implementations.  Thus overlapping moves may yield
               surprises.













































          Rev. C Software Development Set                            Page 3

Museum