malloc(3C)             UNIX System V(C Development Set)              malloc(3C)


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

SYNOPSIS
      #include <stdlib.h>

      void *malloc (sizet size);

      void free (void *ptr);

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

      void *calloc (sizet nelem, sizet elsize);

      void *memalign(sizet alignment, sizet size);

      void *valloc(sizet 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(SCPAGESIZE),size).

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



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malloc(3C)             UNIX System V(C Development Set)              malloc(3C)


      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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