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/*
FUNCTION
	<<memmove>>---move possibly overlapping memory
 
INDEX
	memmove
 
ANSI_SYNOPSIS
	#include <string.h>
	void *memmove(void *<[dst]>, const void *<[src]>, size_t <[length]>);
 
TRAD_SYNOPSIS
	#include <string.h>
	void *memmove(<[dst]>, <[src]>, <[length]>)
	void *<[dst]>;
	void *<[src]>;
	size_t <[length]>;
 
DESCRIPTION
	This function moves <[length]> characters from the block of
	memory starting at <<*<[src]>>> to the memory starting at
	<<*<[dst]>>>. <<memmove>> reproduces the characters correctly
	at <<*<[dst]>>> even if the two areas overlap.
 
 
RETURNS
	The function returns <[dst]> as passed.
 
PORTABILITY
<<memmove>> is ANSI C.
 
<<memmove>> requires no supporting OS subroutines.
 
QUICKREF
	memmove ansi pure
*/
 
#include <string.h>
 
/*SUPPRESS 20*/
_PTR
_DEFUN (memmove, (dst_void, src_void, length),
	_PTR dst_void _AND
	_CONST _PTR src_void _AND
	size_t length)
{
  char *dst = dst_void;
  _CONST char *src = src_void;
 
  if (src < dst && dst < src + length)
    {
      /* Have to copy backwards */
      src += length;
      dst += length;
      while (length--)
	{
	  *--dst = *--src;
	}
    }
  else
    {
      while (length--)
	{
	  *dst++ = *src++;
	}
    }
 
  return dst_void;
}