Re: pkg/56936: posix_openpt(O_RDWR | O_NOCTTY) fails when configuring pkgsrc/x11/mlterm

["David H. Gutteridge" <david%gutteridge.ca@localhost>]

The following reply was made to PR pkg/56936; it has been noted by GNATS.

From: "David H. Gutteridge" <david%gutteridge.ca@localhost>
To: Gnats Bugs <gnats-bugs%netbsd.org@localhost>, dholland%netbsd.org@localhost
Cc: 
Subject: Re: pkg/56936: posix_openpt(O_RDWR | O_NOCTTY) fails when 
 configuring pkgsrc/x11/mlterm
Date: Tue, 06 Sep 2022 18:29:00 -0400

 On Fri, Jul 22, 2022 at 11:20:01AM +0000, rokuyama.rk%gmail.com@localhost wrote:
 > For official package build of pkgsrc-2022Q[12] and -2021Q4 for amd64,
 > i386, and aarch64 (for 9.0), this test failed and configure fell back
 > to old BSD pty.
 > 
 > Also, there is report on netbsd-users@, in which x11/mlterm is
 > misconfigured for NetBSD/amd64 9.2:
 > 
 > https://mail-index.netbsd.org/netbsd-users/2022/07/21/msg028733.html
 > 
 > On the other hand, for pkgsrc-current for NetBSD/amd64 9.0:
 > 
 > http://ftp.netbsd.org/pub/pkgsrc/packages/NetBSD/amd64/.9.0-current-2022-07-15-22.09-being-update/All/mlterm-3.9.2nb3.tgz
 > 
 > this test succeeded, and mlterm uses posix_openpt(3) appropriately.
 > 
 > Also, I could not reproduce the problem by myself for freshly-installed
 > NetBSD/amd64 9.2:
 > 
 > - Manually compiled conftest.c above passes as expected.
 > - x11/mlterm from pkgsrc-2022Q2 is successfully configured to use
 >   posix_openpt(3).
 
 The cause of the issue is that the package uses AC_RUN_IFELSE to check
 if the posix_openpt(3) call *succeeds at runtime[1]*, not just if it
 compiles and links. If the build environment is sandboxed, then the
 call to open /dev/ptmx will fail, and the package will fall back to the
 old "bsd" implementation instead.
 
 The fix would be to remove the runtime check in the configure script,
 if we want it reliably building in official (presumably sandboxed)
 builds. I've had to do that in the past for other packages that did
 something similar.
 
 1. See baselib/configure.in starting at line 279
 
 Dave