42 lines
751 B
ReStructuredText
42 lines
751 B
ReStructuredText
PR_AtomicSet
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============
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Atomically sets a 32-bit value and return its previous contents.
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Syntax
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------
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.. code::
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#include <pratom.h>
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PRInt32 PR_AtomicSet(
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PRInt32 *val,
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PRInt32 newval);
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Parameters
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~~~~~~~~~~
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The function has the following parameter:
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``val``
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A pointer to the value to be set.
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``newval``
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The new value to assign to the ``val`` parameter.
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Returns
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~~~~~~~
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The function returns the prior value of the referenced variable.
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Description
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-----------
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:ref:`PR_AtomicSet` first reads the value of var, then updates it with the
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supplied value. The returned value is the value that was read\ *before*
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memory was updated. The memory modification is unconditional--that is,
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it isn't a test and set operation.
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