MMAP2(2) Linux Programmer's Manual MMAP2(2)NAMEmmap2 - map files or devices into memory
SYNOPSIS
#include <sys/mman.h>
void *mmap2(void *addr, size_t length, int prot,
int flags, int fd, off_t pgoffset);
DESCRIPTION
This is probably not the system call you are interested; instead, see
mmap(2), which describes the glibc wrapper function that invokes this
system call.
The mmap2() system call provides the same interface as mmap(2), except
that the final argument specifies the offset into the file in 4096-byte
units (instead of bytes, as is done by mmap(2)). This enables applica‐
tions that use a 32-bit off_t to map large files (up to 2^44 bytes).
RETURN VALUE
On success, mmap2() returns a pointer to the mapped area. On error -1
is returned and errno is set appropriately.
ERRORS
EFAULT Problem with getting the data from user space.
EINVAL (Various platforms where the page size is not 4096 bytes.) off‐
set * 4096 is not a multiple of the system page size.
mmap2() can also return any of the errors described in mmap(2).
VERSIONSmmap2() is available since Linux 2.3.31.
CONFORMING TO
This system call is Linux-specific.
NOTES
Nowadays, the glibc mmap() wrapper function invokes this system call
rather than the mmap(2) system call.
On ia64, the unit for offset is actually the system page size, rather
than 4096 bytes.
SEE ALSOgetpagesize(2), mmap(2), mremap(2), msync(2), shm_open(3)COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2012-04-16 MMAP2(2)
