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mmap2() - Unix, Linux System Call
mmap2 - map files or devices into memory
void *mmap2(void *start, size_t length, int prot,
int flags, int fd, off_t pgoffset);
mmap2() system call operates in exactly the same way as
except that the final argument specifies the offset into the
file in 4kB units (instead of bytes).
This enables applications that use a 32-bit
off_t to map
larger files (typically up to 2^44 bytes).
mmap2() returns a pointer to the mapped area.
On error -1 is returned
errno is set appropriately.
Problem with getting the
data from userspace.
This system call is Linux specific.
Glibc does not provide a wrapper for this system call; call it using
mmap2() is available since Linux 2.3.31.
It is Linux specific, and should be avoided in portable applications.
On 32-bit systems,
mmap2() is used to implement the
mmap64() function that is part of the LFS (Large File Summit).