3.3 Memory Allocation

void *SMP_Getshmem(size_t size);

• C: gets a piece of shared memory with ``size'' bytes. A pointer to the allocated memory segment is returned.
  
  Restriction: The function is usually called before SMP_Fork. But the function may also be used after SMP_Fork, in which case it must be called by all the processes with the same requested size. The same restriction applies to other shared-memory-allocation routines (including Fortran routines).
• error code: SMP_ERR_MALLOC

SUBROUTINE SMP_GETSHMEM(REFP, KIND, SIZE, IOFF)
<type>  REFP(1)
INTEGER KIND, SIZE
<pointer> IOFF

• Fortran: gets a piece of shared memory for ``kind'' with ``size'' elements.

  <type> 		is the reference type, such as REAL, INTEGER,...
  KIND 		is one of (1,2,4,8,16) as the size of the reference type
  SIZE 		is the number of elements to be allocated
  <pointer> 	is a type large enough to hold an address:
  		for 32-bit, this is INTEGER*4;
  		for 64-bit, this is INTEGER*8.
  

  Reference to the allocated shared memory is done by REFP(IOFF) as the first element. The function may be used after SMP_FORK, but should be called by all the processes with the same requested size.
• error code: SMP_ERR_MALLOC, SMP_ERR_KIND

SUBROUTINE SMP_GETSHMEMP(KIND, SIZE, IPTR)
INTEGER KIND, SIZE
POINTER IPTR

• Fortran: gets a piece of shared memory for ``kind" with ``size" elements.

  KIND		is a positive scaling factor for the size of the data type
  SIZE		is the number of elements to be allocated
  IPTR		is the returned pointer that points to the allocated memory.
  

  This function can be used on platform that supports the Cray pointer. Typically a variable is declared as

     <type>  VAR(100)
     POINTER (IPTR,VAR)
  

  Reference to the allocated shared memory is done by VAR(1) as the first element. The approach works for both 32-bit and 64-bit platforms. Combining with a large value of "kind" this function can be used to allocate memory larger than 2 GB. See SMP_Getshmem() for usage restriction.
• error code: SMP_ERR_MALLOC, SMP_ERR_KIND

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

• C: resets the size of a shared memory buffer that was previously allocated. ``ptr'' points to the old memory buffer and ``size'' is the new size. The function returns a pointer to the newly re-allocated memory buffer. If size=0, the function frees the previously allocated shared memory buffer. The same restriction to SMP_Getshmem applies to this function as well. See SMP_Getshmem() for usage restriction.
• error code: SMP_ERR_MALLOC, SMP_ERR_MEMPTR

SUBROUTINE SMP_RESETSHMEM(REFP, KIND, SIZE, IOFF)
<type>  REFP(1)
INTEGER KIND, SIZE
<pointer> IOFF

• Fortran: resets the size of a shared memory buffer that was previously allocated. See SMP_GETSHMEM for a description on the argument list and SMP_Getshmem() for usage restriction.
• error code: SMP_ERR_MALLOC, SMP_ERR_MEMPTR, SMP_ERR_KIND

SUBROUTINE SMP_RESETSHMEMP(KIND, SIZE, IPTR)
INTEGER KIND, SIZE
POINTER IPTR

• Fortran: resets the size of a shared memory buffer that was previously allocated. See SMP_GETSHMEMP for a description on the argument list and SMP_Getshmem() for usage restriction.
• error code: SMP_ERR_MALLOC, SMP_ERR_MEMPTR, SMP_ERR_KIND

int SMP_Pagesize(void);

INTEGER FUNCTION SMP_PAGESIZE()

• returns the memory page size in bytes.