malloc(3C)          (C Programming Language Utilities)           malloc(3C)


   NAME
         malloc, free, realloc, calloc, memalign, valloc, - memory allocator

   SYNOPSIS
         #include <stdlib.h>

         void *malloc (size_t size);

         void free (void *ptr);

         void *realloc (void *ptr, size_t size);

         void *calloc (size_t nelem, size_t elsize);

         void *memalign(size_t alignment, size_t size);

         void *valloc(size_t size);

   DESCRIPTION
         malloc and free provide a simple general-purpose memory allocation
         package.  malloc returns a pointer to a block of at least size bytes
         suitably aligned for any use.

         The argument to free is a pointer to a block previously allocated by
         malloc, calloc or realloc.  After free is performed this space is
         made available for further allocation.  If ptr is a NULL pointer, no
         action occurs.

         Undefined results will occur if the space assigned by malloc is
         overrun or if some random number is handed to free.

         realloc changes the size of the block pointed to by ptr to size bytes
         and returns a pointer to the (possibly moved) block.  The contents
         will be unchanged up to the lesser of the new and old sizes.  If ptr
         is NULL, realloc behaves like malloc for the specified size.  If size
         is zero and ptr is not a null pointer, the object pointed to is
         freed.

         calloc allocates space for an array of nelem elements of size elsize.
         The space is initialized to zeros.

         memalign allocates size bytes on a specified alignment boundary, and
         returns a pointer to the allocated block.  The value of the returned
         address is guaranteed to be an even multiple of alignment.  Note: the
         value of alignment must be a power of two, and must be greater than
         or equal to the size of a word.

         valloc(size) is equivalent to memalign(sysconf(_SC_PAGESIZE),size)





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   malloc(3C)          (C Programming Language Utilities)           malloc(3C)


         Each of the allocation routines returns a pointer to space suitably
         aligned (after possible pointer coercion) for storage of any type of
         object.

         malloc, realloc, calloc, memalign and valloc will fail if there is
         not enough available memory.

   SEE ALSO
         malloc(3X).

   DIAGNOSTICS
         If there is no available memory, malloc, realloc, memalign, valloc
         and calloc return a null pointer.  When realloc returns NULL, the
         block pointed to by ptr is left intact.  If size, nelem or elsize is
         0, a unique pointer to the arena is returned.






































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