50.3. Determining Memory Residence: mincore()

The mincore() system call is the complement of the memory locking system calls. It reports which pages in a virtual address range are currently resident in RAM, and thus won’t cause a page fault if accessed.

SUSv3 doesn’t specify mincore(). It is available on many, but not all, UNIX implementations. On Linux, mincore() has been available since kernel 2.4.