name : align_b4_memalign.c /* Code fragment of how to get a buffer from the heap that has a specific * alignment. The typical alignment is to a "page" whose size is often * 4096 bytes. */ uint8_t * wrkBuff; /* will get pointer to heap allocation */ uint8_t * wrkPos; /* will get aligned pointer within wrkBuff */ uint32_t sz_of_aligned = 1234; /* number of aligned bytes required */ int psz; #if defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE) psz = sysconf(_SC_PAGESIZE); /* POSIX.1 (was getpagesize()) */ #else psz = 4096; /* give up, pick likely figure */ #endif /* perhaps use posix_memalign() instead. Yes but not always available */ wrkBuff = (uint8_t *)malloc(sz_of_aligned + psz); wrkPos = (uint8_t *)(((sg_uintptr_t)wrkBuff + psz - 1) & (~(psz - 1))); /* The disadvantage of this approach is that it needs both wrkBuff and wrkPos * to be held by the application. The wrkBuff is only needed for the * corresponding free(), all other uses should be via wrkPos. */