<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><br><div><div>On 23 Apr 2014, at 1:02 pm, Russell Allen <<a href="mailto:mail@russell-allen.com">mail@russell-allen.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div id="ygrp-mlmsg" style="font-size: 13px; font-family: Arial, helvetica, clean, sans-serif; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; position: relative;"><div id="ygrp-msg" style="line-height: 1.22em; z-index: 1;"><div id="ygrp-text" style="line-height: 1.22em; font-family: Georgia;"><div style="line-height: 1.22em;"><div style="line-height: 1.22em;"><span style="line-height: 1.22em;">But I'm not happy yet, because I still can't do proper non-pegging IO on OS X - I can't call setOwnerIfFail: on pipes</span></div></div></div></div></div></blockquote><div><br></div>It seems as if not being able to successfully call fcntl(pipe, F_SETOWN, pid) on OS X is not Self's fault but an OS X thing.</div><div><br></div><div>Easiest illustration of this is probably in python:</div><div><br></div><div><pre class="lang-py prettyprint prettyprinted" style="margin-top: 0px; margin-bottom: 10px; padding: 5px; border: 0px; font-size: 14px; vertical-align: baseline; background-color: rgb(238, 238, 238); font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif; overflow: auto; width: auto; max-height: 600px; word-wrap: normal; line-height: 18px;"><code style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif; white-space: inherit;"><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(0, 0, 139);">import</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> os</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> sys</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> fcntl
fcntl</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">fcntl</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">(</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">sys</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">stdin</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> fcntl</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">F_SETOWN</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> os</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">getpid</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">())</span></code></pre><div><br></div></div><div>gives:</div><div><br></div><div><pre class="lang-py prettyprint prettyprinted" style="margin-top: 0px; margin-bottom: 10px; padding: 5px; border: 0px; font-size: 14px; vertical-align: baseline; background-color: rgb(238, 238, 238); font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif; overflow: auto; width: auto; max-height: 600px; word-wrap: normal; line-height: 18px;"><code style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; font-family: Consolas, Menlo, Monaco, 'Lucida Console', 'Liberation Mono', 'DejaVu Sans Mono', 'Bitstream Vera Sans Mono', 'Courier New', monospace, serif; white-space: inherit;"><span class="typ" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(43, 145, 175);">IOError</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">:</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">[</span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(43, 145, 175);">Errno</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> </span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(128, 0, 0);">25</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;">]</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> </span><span class="typ" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(43, 145, 175);">Inappropriate</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> ioctl </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent; color: rgb(0, 0, 139);">for</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; background-color: transparent;"> device</span></code></pre><div><br></div><div>same as for Self. Doing the same on a named pipe gives a 102 error : Operation not supported on socket. Which is interesting given a named pipe isn't a socket.</div><div><br></div><div>I can't find this documented anywhere - nothing in man page for fcntl or Apple bug reports db. I have asked on StackOverflow but no one has answered, though someone did give me a 'student' badge, so that's nice.</div><div><br></div><div><br></div><div>I am at a little bit of a loss here. We need something better than reading in a loop, or doing select with immediate timeout in a loop.</div><div><br></div><div>Russell</div><div><br></div><div><br></div></div></body></html>