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| <section id="shared-memory-file-system"> |
| <h1>Shared Memory File System<a class="headerlink" href="#shared-memory-file-system" title="Permalink to this heading"></a></h1> |
| <p>This supports the POSIX shm_open() APIs for shared memory among unrelated |
| apps.</p> |
| <p>It can be enabled with <code class="docutils literal notranslate"><span class="pre">CONFIG_FS_SHMFS=y</span></code>. To check how it works, please |
| also enable the example app via <code class="docutils literal notranslate"><span class="pre">CONFIG_EXMAPLE_SHM=y</span></code> and run <code class="docutils literal notranslate"><span class="pre">shm_test</span></code> |
| from NSH command line.</p> |
| <p>This file system doesn’t support mount operations though.</p> |
| <p>If comment the line using <code class="docutils literal notranslate"><span class="pre">shm_unlink()</span></code> in the example app, we can see |
| a file under <code class="docutils literal notranslate"><span class="pre">/var/shm/</span></code> from NSH command line after running the example. |
| We can also remove that file from command line.</p> |
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