From: Leefancy <lijian01@kylinos.cn>
Date: Wed, 4 Mar 2026 09:30:12 +0000 (+0800)
Subject: The incorrect order of fcntl() parameters resulted in the inability to clear O_NONBLOCK
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3734e047579fe0b8c254e579a4eaa8de9a026e13;p=thirdparty%2Futil-linux.git

The incorrect order of fcntl() parameters resulted in the inability to clear O_NONBLOCK

Signed-off-by: Leefancy <lijian01@kylinos.cn>
---

diff --git a/term-utils/ttymsg.c b/term-utils/ttymsg.c
index ef7e35899..37ab94c19 100644
--- a/term-utils/ttymsg.c
+++ b/term-utils/ttymsg.c
@@ -136,6 +136,7 @@ ttymsg(struct iovec *iov, size_t iovcnt, char *line, int tmout) {
 		}
 		if (errno == EWOULDBLOCK) {
 			int cpid, flags;
+			int rc;
 			sigset_t sigmask;
 
 			if (forked) {
@@ -161,8 +162,14 @@ ttymsg(struct iovec *iov, size_t iovcnt, char *line, int tmout) {
 			sigemptyset(&sigmask);
 			sigprocmask (SIG_SETMASK, &sigmask, NULL);
 			alarm((u_int)tmout);
-			flags = fcntl(fd, F_GETFL);
-			fcntl(flags, F_SETFL, (long) (flags & ~O_NONBLOCK));
+			rc = flags = fcntl(fd, F_GETFL);
+			if (rc >= 0)
+				rc = fcntl(fd, F_SETFL, (long) (flags & ~O_NONBLOCK));
+			if (rc < 0) {
+				warn(_("fcntl failed: %s"), device); 
+				close_fd(fd);
+				_exit(EXIT_FAILURE);
+			}
 			continue;
 		}
 		/*