mincore(2)                       UNIX System V                       mincore(2)


NAME
      mincore - determine residency of memory pages

SYNOPSIS
      #include <unistd.h>
      int mincore(caddrt addr, sizet len, char *vec);

DESCRIPTION
      mincore returns the primary memory residency status of pages in the
      address space covered by mappings in the range [addr, addr + len).  The
      status is returned as a character-per-page in the character array
      referenced by *vec (which the system assumes to be large enough to
      encompass all the pages in the address range).  The least significant bit
      of each character is set to 1 to indicate that the referenced page is in
      primary memory, 0 if it is not.  The settings of other bits in each
      character are undefined and may contain other information in future
      implementations.

      mincore returns residency information that is accurate at an instant in
      time.  Because the system may frequently adjust the set of pages in
      memory, this information may quickly be outdated.  Only locked pages are
      guaranteed to remain in memory; see memcntl(2).

RETURN VALUE
      mincore returns 0 on success, -1 on failure.

ERRORS
      mincore fails if:

      EFAULT         *vec includes an out-of-range or otherwise inaccessible
                     address.

      EINVAL         addr is not a multiple of the page size as returned by
                     sysconf(3C).

      EINVAL         The argument len has a value less than or equal to 0.

      ENOMEM         Addresses in the range [addr, addr + len) are invalid for
                     the address space of a process, or specify one or more
                     pages which are not mapped.

SEE ALSO
      mlock(3C), mmap(2), sysconf(3C).











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