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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 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).
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 3.53 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)