Click above to get retro games delivered to your door ever month!

realloc

Usage

   #include <stdlib.h>
   void *realloc (void *ptr,size_t size);

   ANSI

Description

   realloc changes the size of a previously allocated memory block pointed
   to by ptr. The size of the block after the call to realloc is specified
   by size. If size is 0, ptr is free'd and NULL is returned. If ptr is
   NULL, then size is malloc'd and the result is returned. If there is
   insufficient room to expand the current block a new block will be
   allocated and the current block released. Existing data will be copied
   into the new block.

Example 

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

   int main()
   {
       char *ptr;
       ptr = realloc(NULL,20*sizeof(char));
       strcpy(ptr,"This is part one, ");
       ptr = realloc(ptr,100*sizeof(char));
       strcat(ptr,"This is part two.");
       printf("\%s\n",ptr);
       realloc(ptr,0);
       return EXIT_SUCCESS;
   }


Return Value

   A pointer to the reallocated memory block is returned. If there is
   insufficient memory for the realloc, NULL is returned (but ptr is not
   free'd).

See Also

   calloc, free, malloc