===================================================================
RCS file: /cvs/mandoc/tag.c,v
retrieving revision 1.20
retrieving revision 1.22
diff -u -p -r1.20 -r1.22
--- mandoc/tag.c	2018/10/23 20:42:37	1.20
+++ mandoc/tag.c	2019/07/10 19:39:01	1.22
@@ -1,6 +1,6 @@
-/*	$Id: tag.c,v 1.20 2018/10/23 20:42:37 schwarze Exp $ */
+/*	$Id: tag.c,v 1.22 2019/07/10 19:39:01 schwarze Exp $ */
 /*
- * Copyright (c) 2015, 2016, 2018 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2015, 2016, 2018, 2019 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -18,6 +18,7 @@
 
 #include <sys/types.h>
 
+#include <errno.h>
 #include <limits.h>
 #include <signal.h>
 #include <stddef.h>
@@ -29,6 +30,7 @@
 
 #include "mandoc_aux.h"
 #include "mandoc_ohash.h"
+#include "mandoc.h"
 #include "tag.h"
 
 struct tag_entry {
@@ -80,8 +82,10 @@ tag_init(void)
 
 	/* Save the original standard output for use by the pager. */
 
-	if ((tag_files.ofd = dup(STDOUT_FILENO)) == -1)
+	if ((tag_files.ofd = dup(STDOUT_FILENO)) == -1) {
+		mandoc_msg(MANDOCERR_DUP, 0, 0, "%s", strerror(errno));
 		goto fail;
+	}
 
 	/* Create both temporary output files. */
 
@@ -89,12 +93,20 @@ tag_init(void)
 	    sizeof(tag_files.ofn));
 	(void)strlcpy(tag_files.tfn, "/tmp/man.XXXXXXXXXX",
 	    sizeof(tag_files.tfn));
-	if ((ofd = mkstemp(tag_files.ofn)) == -1)
+	if ((ofd = mkstemp(tag_files.ofn)) == -1) {
+		mandoc_msg(MANDOCERR_MKSTEMP, 0, 0,
+		    "%s: %s", tag_files.ofn, strerror(errno));
 		goto fail;
-	if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1)
+	}
+	if ((tag_files.tfd = mkstemp(tag_files.tfn)) == -1) {
+		mandoc_msg(MANDOCERR_MKSTEMP, 0, 0,
+		    "%s: %s", tag_files.tfn, strerror(errno));
 		goto fail;
-	if (dup2(ofd, STDOUT_FILENO) == -1)
+	}
+	if (dup2(ofd, STDOUT_FILENO) == -1) {
+		mandoc_msg(MANDOCERR_DUP, 0, 0, "%s", strerror(errno));
 		goto fail;
+	}
 	close(ofd);
 
 	/*
@@ -216,7 +228,13 @@ tag_write(void)
 
 	if (tag_files.tfd <= 0)
 		return;
-	stream = fdopen(tag_files.tfd, "w");
+	if (tag_files.tagname != NULL && ohash_find(&tag_data,
+            ohash_qlookup(&tag_data, tag_files.tagname)) == NULL) {
+		mandoc_msg(MANDOCERR_TAG, 0, 0, "%s", tag_files.tagname);
+		tag_files.tagname = NULL;
+	}
+	if ((stream = fdopen(tag_files.tfd, "w")) == NULL)
+		mandoc_msg(MANDOCERR_FDOPEN, 0, 0, "%s", strerror(errno));
 	entry = ohash_first(&tag_data, &slot);
 	while (entry != NULL) {
 		if (stream != NULL && entry->prio >= 0)