set the close-on-exec flag for newly opened files

Reason:
 vi uses flock to help you notice when you are already editing a file.

 But, when using :shell or :! the fdesc for the locked file is inherited by
 the subprocess.

 This means that if you (say) do a :!xterm& and then quit vi, the fdesc is
 kept open by the xterm and the lock is never released. future vi's on
 that file will then complain.

 I sent this off to bostic.com a long time ago but have as yet heard nothing.

1 files changed, 4 insertions, 0 deletions

diff --git a/usr.bin/vi/common/exf.c b/usr.bin/vi/common/exf.c
index 574a16aab3b..dd0eba7fd87 100644
--- a/usr.bin/vi/common/exf.c
+++ b/usr.bin/vi/common/exf.c
@@ -1436,6 +1436,10 @@ file_lock(sp, name, fdp, fd, iswrite)
 	if (!O_ISSET(sp, O_LOCKFILES))
 		return (LOCK_SUCCESS);
 	
+	/* Set close-on-exec flag so locks are not inherited by shell cmd. */
+	if (fcntl(fd, F_SETFD, 1) == -1)
+		msgq_str(sp, M_SYSERR, name, "%s");
+
 #ifdef HAVE_LOCK_FLOCK			/* Hurrah!  We've got flock(2). */
 	/*
 	 * !!!