58 lines
1.3 KiB
ReStructuredText
58 lines
1.3 KiB
ReStructuredText
PR_OpenSemaphore
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================
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Creates or opens a named semaphore with the specified name.
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Syntax
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------
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.. code::
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#include <pripcsem.h>
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#define PR_SEM_CREATE 0x1 /* create if not exist */
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#define PR_SEM_EXCL 0x2 /* fail if already exists */
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NSPR_API(PRSem *) PR_OpenSemaphore(
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const char *name,
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PRIntn flags,
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PRIntn mode,
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PRUintn value
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);
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Parameters
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~~~~~~~~~~
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The function has the following parameters:
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``name``
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The name to be given the semaphore.
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``flags``
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How to create or open the semaphore.
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``mode``
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Unix style file mode to be used when creating the semaphore.
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``value``
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The initial value assigned to the semaphore.
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Returns
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~~~~~~~
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A pointer to a PRSem structure or ``NULL/code> on error.``
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Description
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~~~~~~~~~~~
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If the named semaphore doesn't exist and the ``PR_SEM_CREATE`` flag is
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specified, the named semaphore is created. The created semaphore needs
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to be removed from the system with a :ref:`PR_DeleteSemaphore` call.
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If ``PR_SEM_CREATE`` is specified, the third argument is the access
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permission bits of the new semaphore (same interpretation as the mode
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argument to :ref:`PR_Open`) and the fourth argument is the initial value of
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the new semaphore. ``If PR_SEM_CREATE`` is not specified, the third and
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fourth arguments are ignored.
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