NAME    [Toc]    [Back]

     mincore - determine residency of memory pages

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <sys/mman.h>

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

DESCRIPTION    [Toc]    [Back]

     The mincore() system call allows a process to obtain information about
     whether pages are core resident.  The status of the memory range is
     returned in the character-per-page array vec.  If the page is resident,
     the least significant bit of the corresponding character in vec will be
     set.  Other bits are reserved for additional information which future
     implementations may return.

     Note that the status of each page may change between the call to
     mincore() and the return of the page status information.  In order to
     guarantee that pages will remain in core, the address range must be
     locked with mlock(2).

RETURN VALUES    [Toc]    [Back]

     mincore() returns 0 on success, or -1 on failure and sets the variable
     errno to indicate the error.

ERRORS    [Toc]    [Back]

     The mincore() call will fail if:

     [EFAULT]           vec points to an illegal address.

     [EINVAL]           addr is not a multiple of the system page size.

     [EINVAL]           len is equal to 0.

     [ENOMEM]           The address range specified is invalid for the calling
                        process, or one or more of the pages specified in the
                        range are not mapped.

SEE ALSO    [Toc]    [Back]

     madvise(2), mlock(2), mprotect(2), msync(2), munmap(2), sysconf(3)

HISTORY    [Toc]    [Back]

     The mincore() function first appeared in 4.4BSD.

BSD                              June 6, 1999                              BSD