MMAP2

NAME

mmap2 - map files or devices into memory

SYNOPSIS

#include <sys/mman.h>
#include <syscall.h>

_syscall6(void *, start, size_t, length, int, prot, int, flags, int, fd, off_t, pgoffset);

void * mmap2(void *start, size_t length, int prot, int flags, int fd, off_t pgoffset);

#endif

DESCRIPTION

The function mmap2 operates in exactly the same way as mmap(2), except that the final argument specifies the offset into the file in units of the system page size (instead of bytes). This enables applications that use a 32-bit off_t to map larger files (typically 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 userspace.

NOTES

The function mmap2 is available since Linux 2.3.31. It is Linux specific, and should be avoided in portable applications. See also the mmap64() function that is part of the LFS (Large File Summit).