The following function sets, modeled after the ANSI C standard,
but specifying behavior when requesting zero bytes,
are available for allocating and releasing memory from the Python heap:
void* PyMem_Malloc(
size_t n)
Allocates n bytes and returns a pointer of type void*
to the allocated memory, or NULL if the request fails.
Requesting zero bytes returns a distinct non-NULL pointer if
possible, as if PyMem_Malloc(1) had been called instead.
The memory will not have been initialized in any way.
void* PyMem_Realloc(
void *p, size_t n)
Resizes the memory block pointed to by p to n bytes.
The contents will be unchanged to the minimum of the old and the new
sizes. If p is NULL, the call is equivalent to
PyMem_Malloc(n); else if n is equal to zero, the
memory block is resized but is not freed, and the returned pointer
is non-NULL. Unless p is NULL, it must have been
returned by a previous call to PyMem_Malloc() or
PyMem_Realloc().
void PyMem_Free(
void *p)
Frees the memory block pointed to by p, which must have been
returned by a previous call to PyMem_Malloc() or
PyMem_Realloc(). Otherwise, or if
PyMem_Free(p) has been called before, undefined
behavior occurs. If p is NULL, no operation is performed.
The following type-oriented macros are provided for convenience. Note
that TYPE refers to any C type.
TYPE* PyMem_New(
TYPE, size_t n)
Same as PyMem_Malloc(), but allocates (n *
sizeof(TYPE)) bytes of memory. Returns a pointer cast to
TYPE*. The memory will not have been initialized in
any way.
TYPE* PyMem_Resize(
void *p, TYPE, size_t n)
Same as PyMem_Realloc(), but the memory block is resized
to (n * sizeof(TYPE)) bytes. Returns a pointer
cast to TYPE*.
void PyMem_Del(
void *p)
Same as PyMem_Free().
In addition, the following macro sets are provided for calling the
Python memory allocator directly, without involving the C API functions
listed above. However, note that their use does not preserve binary
compatibility across Python versions and is therefore deprecated in
extension modules.
