Improve handling of flushing for non-fatal files.

3 files changed, 33 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 3cf9ddab..ae69b7e2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2017-03-24         Arnold D. Robbins     <arnold@skeeve.com>
+
+	* builtin.c (efwrite): Exit successfully upon EPIPE, as SIGPIPE
+	done. Improve error messages upon failure to write.
+	(do_fflush): Update ERRNO for non-fatal flush failures.
+	* io.c (non_fatal_flush_std_file): Update ERRNO when flush is
+	non-fatal.
+	(flush_io): If a redirect is marked non-fatal, only warning,
+	not fatal message.
+
 2017-03-23         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* config.sub: Updated again.
diff --git a/builtin.c b/builtin.c
index b92eb19d..0f2c62f8 100644
--- a/builtin.c
+++ b/builtin.c
@@ -131,14 +131,18 @@ wrerror:
 #endif
 	/* die silently on EPIPE to stdout */
 	if (fp == stdout && errno == EPIPE)
-		gawk_exit(EXIT_FATAL);
+		gawk_exit(EXIT_SUCCESS);	// a la SIGPIPE
 
 	/* otherwise die verbosely */
 	if ((rp != NULL) ? is_non_fatal_redirect(rp->value, strlen(rp->value)) : is_non_fatal_std(fp))
 		update_ERRNO_int(errno);
 	else
 		fatal(_("%s to \"%s\" failed (%s)"), from,
-			rp ? rp->value : _("standard output"),
+			rp != NULL
+				? rp->value
+				: fp == stdout
+					? _("standard output")
+					: _("standard error"),
 			errno ? strerror(errno) : _("reason unknown"));
 }
 
@@ -214,7 +218,7 @@ do_fflush(int nargs)
 
 	/* fflush() */
 	if (nargs == 0) {
-		status = flush_io();
+		status = flush_io();	// ERRNO updated
 		return make_number((AWKNUM) status);
 	}
 
@@ -224,7 +228,7 @@ do_fflush(int nargs)
 
 	/* fflush("") */
 	if (tmp->stlen == 0) {
-		status = flush_io();
+		status = flush_io();	// ERRNO updated
 		DEREF(tmp);
 		return make_number((AWKNUM) status);
 	}
@@ -251,6 +255,7 @@ do_fflush(int nargs)
 				if (! is_non_fatal_redirect(tmp->stptr, tmp->stlen))
 					fatal(_("fflush: cannot flush file `%.*s': %s"),
 						len, file, strerror(errno));
+				update_ERRNO_int(errno);
 			}
 		} else if ((rp->flag & RED_TWOWAY) != 0)
 				warning(_("fflush: cannot flush: two-way pipe `%.*s' has closed write end"),
diff --git a/io.c b/io.c
index 0da27575..00a0ba3c 100644
--- a/io.c
+++ b/io.c
@@ -1407,6 +1407,7 @@ non_fatal_flush_std_file(FILE *fp)
 					: _("fflush: cannot flush standard error: %s"),
 						strerror(errno));
 		} else {
+			update_ERRNO_int(errno);
 			warning(fp == stdout
 				? _("error writing standard output (%s)")
 				: _("error writing standard error (%s)"),
@@ -1427,26 +1428,34 @@ flush_io()
 	int status = 0;
 
 	errno = 0;
-	if (! non_fatal_flush_std_file(stdout))
+	if (! non_fatal_flush_std_file(stdout))	// ERRNO updated
 		status++;
 
 	errno = 0;
-	if (! non_fatal_flush_std_file(stderr))
+	if (! non_fatal_flush_std_file(stderr))	// ERRNO updated
 		status++;
 
+
 	// now for all open redirections
 	for (rp = red_head; rp != NULL; rp = rp->next) {
+		void (*messagefunc)(const char *mesg, ...) = fatal;
+
 		/* flush both files and pipes, what the heck */
 		if ((rp->flag & RED_WRITE) != 0 && rp->output.fp != NULL) {
 			if (rp->output.gawk_fflush(rp->output.fp, rp->output.opaque) != 0) {
+				update_ERRNO_int(errno);
+
+				if (is_non_fatal_redirect(rp->value, strlen(rp->value)))
+					messagefunc = warning;
+
 				if ((rp->flag & RED_PIPE) != 0)
-					warning(_("pipe flush of `%s' failed (%s)."),
+					messagefunc(_("pipe flush of `%s' failed (%s)."),
 						rp->value, strerror(errno));
 				else if ((rp->flag & RED_TWOWAY) != 0)
-					warning(_("co-process flush of pipe to `%s' failed (%s)."),
+					messagefunc(_("co-process flush of pipe to `%s' failed (%s)."),
 						rp->value, strerror(errno));
 				else
-					warning(_("file flush of `%s' failed (%s)."),
+					messagefunc(_("file flush of `%s' failed (%s)."),
 						rp->value, strerror(errno));
 				status++;
 			}