from small one page howto to huge articles all in one place
poll results
Last additions:
May 25th. 2007:
April, 26th. 2006:
| You are here: manpages
POSIX_MEM_OFFSET
Section: POSIX Programmer's Manual (3P)
Updated: 2003
Index
Return to Main Contents
PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
NAME
posix_mem_offset - find offset and length of a mapped typed memory
block (ADVANCED REALTIME)
SYNOPSIS
#include <sys/mman.h>
int posix_mem_offset(const void *restrict addr, size_t
len,
off_t *restrict off, size_t *restrict
contig_len,
int *restrict fildes);
DESCRIPTION
The posix_mem_offset() function shall return in the variable
pointed to by off a value that identifies the offset
(or location), within a memory object, of the memory block currently
mapped at addr. The function shall return in the
variable pointed to by fildes, the descriptor used (via mmap())
to establish the
mapping which contains addr. If that descriptor was closed since
the mapping was established, the returned value of
fildes shall be -1. The len argument specifies the length
of the block of the memory object the user wishes the
offset for; upon return, the value pointed to by contig_len
shall equal either len, or the length of the largest
contiguous block of the memory object that is currently mapped to
the calling process starting at addr, whichever is
smaller.
If the memory object mapped at addr is a typed memory object,
then if the off and contig_len values
obtained by calling posix_mem_offset() are used in a call to
mmap() with a file
descriptor that refers to the same memory pool as fildes (either
through the same port or through a different port), and
that was opened with neither the POSIX_TYPED_MEM_ALLOCATE nor the
POSIX_TYPED_MEM_ALLOCATE_CONTIG flag, the typed memory area that
is mapped shall be exactly the same area that was mapped at addr
in the address space of the process that called
posix_mem_offset().
If the memory object specified by fildes is not a typed memory
object, then the behavior of this function is
implementation-defined.
RETURN VALUE
Upon successful completion, the posix_mem_offset() function
shall return zero; otherwise, the corresponding error status
value shall be returned.
ERRORS
The posix_mem_offset() function shall fail if:
- EACCES
-
The process has not mapped a memory object supported by this function
at the given address addr.
This function shall not return an error code of [EINTR].
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
mmap(), posix_typed_mem_open(), the Base
Definitions volume of IEEE Std 1003.1-2001, <sys/mman.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
Index
- PROLOG
-
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ERRORS
-
- EXAMPLES
-
- APPLICATION USAGE
-
- RATIONALE
-
- FUTURE DIRECTIONS
-
- SEE ALSO
-
- COPYRIGHT
-
Please read "Why adblockers are badwww.cars2fast4u.de
|
Other free services .
.
| 
|
|
- Running on 
-
:
: 
