66 lines
1.4 KiB
ReStructuredText
66 lines
1.4 KiB
ReStructuredText
PR_CreateFileMap
|
|
================
|
|
|
|
Creates a file mapping object.
|
|
|
|
|
|
Syntax
|
|
------
|
|
|
|
.. code::
|
|
|
|
#include <prio.h>
|
|
|
|
PRFileMap* PR_CreateFileMap(
|
|
PRFileDesc *fd,
|
|
PRInt64 size,
|
|
PRFileMapProtect prot);
|
|
|
|
|
|
Parameters
|
|
~~~~~~~~~~
|
|
|
|
The function has the following parameters:
|
|
|
|
``fd``
|
|
A pointer to a :ref:`PRFileDesc` object representing the file that is to
|
|
be mapped to memory.
|
|
``size``
|
|
Size of the file specified by ``fd``.
|
|
``prot``
|
|
Protection option for read and write accesses of a file mapping. This
|
|
parameter consists of one of the following options:
|
|
|
|
- :ref:`PR_PROT_READONLY`. Read-only access.
|
|
- :ref:`PR_PROT_READWRITE`. Readable, and write is shared.
|
|
- :ref:`PR_PROT_WRITECOPY`. Readable, and write is private
|
|
(copy-on-write).
|
|
|
|
|
|
Returns
|
|
~~~~~~~
|
|
|
|
- If successful, a file mapping of type :ref:`PRFileMap`.
|
|
- If unsuccessful, ``NULL``.
|
|
|
|
|
|
Description
|
|
-----------
|
|
|
|
The ``PRFileMapProtect`` enumeration used in the ``prot`` parameter is
|
|
defined as follows:
|
|
|
|
.. code::
|
|
|
|
typedef enum PRFileMapProtect {
|
|
PR_PROT_READONLY,
|
|
PR_PROT_READWRITE,
|
|
PR_PROT_WRITECOPY
|
|
} PRFileMapProtect;
|
|
|
|
:ref:`PR_CreateFileMap` only prepares for the mapping a file to memory. The
|
|
returned file-mapping object must be passed to :ref:`PR_MemMap` to actually
|
|
map a section of the file to memory.
|
|
|
|
The file-mapping object should be closed with a :ref:`PR_CloseFileMap` call
|
|
when it is no longer needed.
|