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<concept id="GUID-BA89F4DF-E2F6-5E0B-BF20-F8898FC5D5F8" xml:lang="en"><title>Mutexes

Overview</title><shortdesc>This document provides an overview of mutexes.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<section id="GUID-C50B1D56-F467-42DB-B010-1B37E5CC39EC"><title>Purpose</title> <p>Synchronises exclusive access to shared

resources within and between processes.</p> </section>

<section id="GUID-A4DD591F-A0D2-4FA5-9AFC-6D7DC76C9F2C"><title>Description</title> <p>Mutexes are typically used to serialise

access to a section of re-entrant code that cannot be executed concurrently

by more than one thread. A mutex object only allows one thread into a controlled

section, forcing other threads which attempt to gain access to that section

to wait until the first thread has exited from that section.</p> <p>A mutex

can be used by threads across any number of processes. If a resource is only

shared between the threads within the same process, it can be more efficient

to use a critical section.</p> <p>Mutexes are Kernel objects and, as such,

are managed by the Kernel, and accessed by user programs through handles. </p> <p>The

mutex handle is provided by <xref href="GUID-C0FEA3A0-7DD3-3B87-A919-CB973BC05766.dita"><apiname>RMutex</apiname></xref>.</p> <p><xref href="GUID-A907C7B1-BD90-3E8F-AEA8-5A634BC98D0D.dita"><apiname>TFindMutex</apiname></xref> is

used for finding a mutex created by another process.</p> </section>