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PONSTask subprocess stuck in _dyld_start
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copied!<p>I use <em>NSTask</em> to run my helper application. On 99% one my customer systems this works fine, but two got back to me letting me know it doesn't. One of them was nice enough to let me look into the issue per remote desktop.</p> <p>I tried a lot of different <em>NSPipe/NSFileHandle</em> combination for StandardOutput/StandardError to make sure the problem is not related filling up these buffers. Example <a href="http://cocoadev.com/wiki/WrappingUnixApps" rel="noreferrer">1</a> and <a href="http://cocoadev.com/wiki/NSTaskWaitUntilExit" rel="noreferrer">2</a>. My guess is that it is not related because it works fine on so many systems and _dyld_start is too early on in the application lifecycle to fill up StandardOutput/StandardError.</p> <p>Other notes about the problem:</p> <ul> <li>Launching the helper app from the terminal works fine.</li> <li>Attaching and detaching the gdb on the stuck process and after-worth it works fine and when it finished <em>NSTask</em> picks up work after <em>-waitUntilExit</em>.</li> <li>Using <em>fork(2)</em> and <em>execv(3)</em> instead of <em>NSTask</em> is able to launch and run the helper fine.</li> <li>The parent process is sandboxed but I think previous reports where non-sandboxed on Mac OS X 10.6/10.7.</li> </ul> <p>Screenshot of the process Sample from Activity Monitor:</p> <p><img src="https://i.stack.imgur.com/a4nl9.png" alt="Activity Monitor"> </p> <p>Any clues or debugging tips to figure out why the helper is stuck in _dyld_start are welcome!</p>

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