Section: Linux Programmer's Manual (2)
mmap2 - map files or devices into memory
void *mmap2(void *addr, size_t length, int prot,
int flags, int fd, off_t pgoffset);
This is probably not the system call that you are interested in; instead, see
which describes the glibc wrapper function that invokes this system call.
system call provides the same interface 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 user space.
(Various platforms where the page size is not 4096 bytes.)
offset * 4096
is not a multiple of the system page size.
can also return any of the errors described in
is available since Linux 2.3.31.
This system call is Linux-specific.
On architectures where this system call is present,
wrapper function invokes this system call rather than the
This system call does not exist on x86-64.
On ia64, the unit for
is actually the system page size, rather than 4096 bytes.
This page is part of release 5.10 of the Linux
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