NAME
mincore —
determine residency of memory
pages
LIBRARY
library “libc”
SYNOPSIS
#include
<sys/mman.h>
int
mincore(const
void *addr, size_t
len, char
*vec);
DESCRIPTION
Themincore()
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may be out of date by the time the system call returns.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.