<div dir="ltr">Interesting. Probably because our previous for-loop takes input from regular file. The GNU implementation seems to treat only special files (block and char devices) differently as a "magnetic tape".<br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Apr 20, 2021 at 5:33 PM Rob Landley <<a href="mailto:rob@landley.net">rob@landley.net</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On 4/20/21 3:23 AM, Yi-yo Chiang via Toybox wrote:<br>
> Why do we need setsid in the new cpio testcase though?<br>
<br>
Because without it TEST_HOST=1 calls the gnu/dammit cpio which does:<br>
<br>
  $ cpio -i < /dev/null<br>
  Found end of tape.  To continue, type device/file name when ready.<br>
<br>
And then hangs waiting for you to hit enter after changing a nonexistent<br>
reel-to-reel magnetic tape. The setsid breaks the association with /dev/tty so<br>
opening it fails and thus cpio returns immediately.<br>
<br>
(I.E. I have no idea how your previous for loop working around the TRAILER!!!<br>
behavior ever worked. I'm guessing you never ran that script from a context with<br>
a controlling tty?)<br>
<br>
Rob<br>
</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><table width="90%" border="0" cellspacing="0" cellpadding="0" style="margin:0px;padding:0px;font-family:"Times New Roman";max-width:348px"><tbody style="margin:0px;padding:0px"><tr style="margin:0px;padding:0px"><td style="padding:0px"><table border="0" cellspacing="0" cellpadding="0" style="margin:0px;padding:20px 0px 0px"><tbody style="margin:0px;padding:0px"><tr style="margin:0px;padding:0px"><td valign="top" style="padding:0px 20px 0px 0px;vertical-align:top;border-right:1px solid rgb(213,213,213)"><img src="https://i.imgur.com/eGpkLls.png" width="200" height="64"><br></td><td style="padding:0px 0px 0px 20px"><table border="0" cellspacing="0" cellpadding="0" style="margin:0px;padding:0px"><tbody style="margin:0px;padding:0px"><tr style="margin:0px;padding:0px"><td colspan="2" style="font-family:Arial,Helvetica,Verdana,sans-serif;padding:1px 0px 5px;font-size:13px;line-height:13px;color:rgb(56,58,53);font-weight:700">Yi-yo Chiang</td></tr><tr style="margin:0px;padding:0px"><td colspan="2" style="font-family:Arial,Helvetica,Verdana,sans-serif;padding:0px 0px 5px;font-size:11px;line-height:13px;color:rgb(56,58,53)">Software Engineer</td></tr><tr style="margin:0px;padding:0px"><td colspan="2" style="font-family:Arial,Helvetica,Verdana,sans-serif;padding:0px 0px 5px;font-size:11px;line-height:13px;color:rgb(56,58,53)"><a href="mailto:yochiang@google.com" target="_blank">yochiang@google.com</a></td></tr><tr style="margin:0px;padding:0px"><td colspan="2" style="font-family:Arial,Helvetica,Verdana,sans-serif;padding:0px 0px 3px;font-size:11px;line-height:13px;color:rgb(3,112,248)"></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></div></div>