scroll

commit 1dbf2dce08892df710645ddbd2ce12759ec95078
parent 58c58743d8f391ef0e4776fc46d92c824795d162
Author: Jan Klemkow <j.klemkow@wemelug.de>
Date:   Thu, 30 Apr 2020 22:12:50 +0200

fix race condition between sigwinch and sigchld

sigwinch died if it tries to set the window size
to a file descriptor of an exited child.  Thus,
we just ignore this error in that situation.

Diffstat:
M
scroll.c
 | 
5
++++-

1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/scroll.c b/scroll.c
@@ -96,8 +96,11 @@ sigwinch(int sig)
 
 	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1)
 		die("ioctl:");
-	if (ioctl(mfd, TIOCSWINSZ, &ws) == -1)
+	if (ioctl(mfd, TIOCSWINSZ, &ws) == -1) {
+		if (errno == EBADF)	/* child already exited */
+			return;
 		die("ioctl:");
+	}
 	kill(-child, SIGWINCH);
 	doredraw = true;
 }