MMAP2(2)						     Linux Programmer's Manual							  MMAP2(2)

NAME

       mmap2 - 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 applications 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.)  offset * 4096 is not a multiple of the system page size.

       mmap2() can also return any of the errors described in mmap(2).

VERSIONS

       mmap2() 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 ALSO

       getpagesize(2), mmap(2), mremap(2), msync(2), shm_open(3)

COLOPHON

       This page is part of release 3.44 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)