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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alexander Best <alexbestms@math.uni-muenster.de>
References: <permail-20091023104227f0889e8400002915-a_best01@message-id.uni-muenster.de>
Date: Fri, 23 Oct 2009 14:02:38 +0200
In-Reply-To: <permail-20091023104227f0889e8400002915-a_best01@message-id.uni-muenster.de>
	(Alexander Best's message of "Fri, 23 Oct 2009 12:42:27 +0200 (CEST)")
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Cc: Antony Mawer <lists@mawer.org>, freebsd-hackers@freebsd.org,
	pluknet <pluknet@gmail.com>, ed@freebsd.org, rafan@freebsd.org
Subject: Re: help needed to fix contrib/ee crash/exit when receiving SIGWINCH
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[cc: ed for ee and rafan for ncurses]

Alexander Best <alexbestms@math.uni-muenster.de> writes:
> i'm not so sure this is entirely ee's fault.

It is *partly* ee's fault.

src/usr.bin/ee/ee.c in 7:

                in =3D wgetch(text_win);
                if (in =3D=3D -1)
                        continue;

src/contrib/ee/ee.c in 8:

                in =3D wgetch(text_win);
                if (in =3D=3D -1)
                        exit(0);  /* without this exit ee will go into an=20
                                     infinite loop if the network=20
                                     session detaches */

>From the wgetch() man page:

       Programmers concerned about portability should be prepared  for  eit=
her
       of  two  cases: (a) signal receipt does not interrupt getch; (b) sig=
nal
       receipt interrupts getch and causes it to return ERR with errno set =
 to
       EINTR.   Under the ncurses implementation, handled signals never int=
er=E2=80=90
       rupt getch.

so ee is not portable (it should not assume that a "handled signal" such
as SIGWINCH does not interrupt wgetch()), but that's not the real issue.

The real issue, though, is that when a SIGWINCH is caught, wgetch()
correctly returns KEY_RESIZE, but the next call to wgetch() returns -1.
The next call after that is fine.  I suspect the error lies somewhere
inside kgetch() in contrib/ncurses/ncurses/base/lib_getch.c.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no