[PATCH iptables] print warnings to stderr

iptables prints some of its error messages and warnings to stdout.
This patch applies to svn r7075 and will make iptables print
diagnostic messages to stderr instead.

Signed-off-by: Max Kellermann <max@duempel.org>

3 files changed, 16 insertions, 12 deletions

diff --git a/ip6tables.c b/ip6tables.c
index f658fc7a..938c91ee 100644
--- a/ip6tables.c
+++ b/ip6tables.c
@@ -1592,9 +1592,10 @@ int do_command6(int argc, char *argv[], char **table, ip6tc_handle_t *handle)
 			
 			if (is_exthdr(fw.ipv6.proto)
 			    && (fw.ipv6.invflags & IP6T_INV_PROTO) == 0)
-				printf("Warning: never matched protocol: %s. "
-				       "use extension match instead.\n",
-				       protocol);
+				fprintf(stderr,
+					"Warning: never matched protocol: %s. "
+					"use extension match instead.\n",
+					protocol);
 			break;
 
 		case 's':
@@ -1753,7 +1754,7 @@ int do_command6(int argc, char *argv[], char **table, ip6tc_handle_t *handle)
 				optarg[0] = '\0';
 				continue;
 			}
-			printf("Bad argument `%s'\n", optarg);
+			fprintf(stderr, "Bad argument `%s'\n", optarg);
 			exit_tryhelp(2);
 
 		default:
@@ -1926,8 +1927,9 @@ int do_command6(int argc, char *argv[], char **table, ip6tc_handle_t *handle)
 		}
 
 		if (target && ip6tc_is_chain(jumpto, *handle)) {
-			printf("Warning: using chain %s, not extension\n",
-			       jumpto);
+			fprintf(stderr,
+				"Warning: using chain %s, not extension\n",
+				jumpto);
 
 			if (target->t)
 				free(target->t);
diff --git a/iptables.c b/iptables.c
index 25ca3583..7096121c 100644
--- a/iptables.c
+++ b/iptables.c
@@ -1818,7 +1818,7 @@ int do_command(int argc, char *argv[], char **table, iptc_handle_t *handle)
 				optarg[0] = '\0';
 				continue;
 			}
-			printf("Bad argument `%s'\n", optarg);
+			fprintf(stderr, "Bad argument `%s'\n", optarg);
 			exit_tryhelp(2);
 
 		default:
@@ -1990,8 +1990,9 @@ int do_command(int argc, char *argv[], char **table, iptc_handle_t *handle)
 		}
 
 		if (target && iptc_is_chain(jumpto, *handle)) {
-			printf("Warning: using chain %s, not extension\n",
-			       jumpto);
+			fprintf(stderr,
+				"Warning: using chain %s, not extension\n",
+				jumpto);
 
 			if (target->t)
 				free(target->t);
diff --git a/xtables.c b/xtables.c
index 58b4e81b..6107119f 100644
--- a/xtables.c
+++ b/xtables.c
@@ -246,9 +246,10 @@ void parse_interface(const char *arg, char *vianame, unsigned char *mask)
 			if (vianame[i] == ':' ||
 			    vianame[i] == '!' ||
 			    vianame[i] == '*') {
-				printf("Warning: weird character in interface"
-				       " `%s' (No aliases, :, ! or *).\n",
-				       vianame);
+				fprintf(stderr,
+					"Warning: weird character in interface"
+					" `%s' (No aliases, :, ! or *).\n",
+					vianame);
 				break;
 			}
 		}