posix_memalign - aligned memory allocation (ADVANCED REALTIME)
The posix_memalign() function shall allocate size bytes aligned on a boundary specified by alignment, and shall return a pointer to the allocated memory in memptr. The value of alignment shall be a power of two multiple of sizeof( void *).
Upon successful completion, the value pointed to by memptr shall be a multiple of alignment.
If the size of the space requested is 0, the behavior is implementation-defined; the value returned in memptr shall be either a null pointer or a unique pointer.
[CX] The free() function shall deallocate memory that has previously been allocated by posix_memalign().
Upon successful completion, posix_memalign() shall return zero; otherwise, an error number shall be returned to indicate the error.
The posix_memalign() function shall fail if:
- The value of the alignment parameter is not a power of two multiple of sizeof( void *).
- There is insufficient memory available with the requested alignment.
The posix_memalign() function is part of the Advisory Information option and need not be provided on all implementations.
free , malloc
First released in Issue 6. Derived from IEEE Std 1003.1d-1999.
In the SYNOPSIS, the inclusion of <sys/types.h> is no longer required.
Austin Group Interpretation 1003.1-2001 #058 is applied, clarifying the value of the alignment argument in the DESCRIPTION.
Austin Group Interpretation 1003.1-2001 #152 is applied, clarifying the behavior when the size of the space requested is 0.
return to top of page