Section: Linux Programmer's Manual (2)
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mmap2 - map files or devices into memory
void *mmap2(void *addr, size_t length, int prot,
int flags, int fd, off_t pgoffset);
system call operates in exactly the same way as
except that the final argument specifies the offset into the
file in 4096-byte units (instead of bytes, as is done by
This enables applications that use a 32-bit
to map large files (up to 2^44 bytes).
returns a pointer to the mapped area.
On error -1 is returned and
is set appropriately.
Problem with getting the data from userspace.
(Various platforms where the page size is not 4096 bytes.)
offset * 4096
is not a multiple of the system page size.
can return any of the same errors as
is available since Linux 2.3.31.
This system call is Linux-specific.
Nowadays, the glibc
wrapper function invokes this system call rather than the
On ia64, the unit for
is actually the system page size, rather than 4096 bytes.
This page is part of release 3.27 of the Linux
A description of the project,
and information about reporting bugs,
can be found at
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This document was created by
using the manual pages.