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NAME
     mincore — determine residency of memory pages


LIBRARY
     Standard C Library (libc, -lc)


SYNOPSIS
     #include <sys/mman.h>

     int
     mincore(const void *addr, size_t len, char *vec);


DESCRIPTION
     The mincore() system call determines whether each of the pages in the region beginning at addr and
     continuing for len bytes is resident.  The status is returned in the vec array, one character per page.
     Each character is either 0 if the page is not resident, or a combination of the following flags (defined in
     <sys/mman.h>):

     MINCORE_INCORE            Page is in core (resident).

     MINCORE_REFERENCED        Page has been referenced by us.

     MINCORE_MODIFIED          Page has been modified by us.

     MINCORE_REFERENCED_OTHER  Page has been referenced.

     MINCORE_MODIFIED_OTHER    Page has been modified.

     MINCORE_SUPER             Page is part of a large (“super”) page.

     The information returned by mincore() may be out of date by the time the system call returns.  The only way
     to ensure that a page is resident is to lock it into memory with the mlock(2) system call.


RETURN VALUES
     The mincore() function returns the value 0 if successful; otherwise the value -1 is returned and the global
     variable errno is set to indicate the error.


ERRORS
     The mincore() system call will fail if:

     [ENOMEM]           The virtual address range specified by the addr and len arguments is not fully mapped.

     [EFAULT]           The vec argument points to an illegal address.


SEE ALSO
     madvise(2), mlock(2), mprotect(2), msync(2), munmap(2), getpagesize(3)


HISTORY
     The mincore() system call first appeared in 4.4BSD.