Add --test option.

This will be used to control the printing of test messages that say when
a connection is ready to use, to reduce delays in ncat-test.

ncat/ncat_core.c

@@ -191,6 +191,8 @@ void options_init(void)
 
     o.nsock_engine = 0;
 
+    o.test = 0;
+
     o.numsrcrtes = 0;
     o.srcrteptr = 4;
 

ncat/ncat_core.h

@@ -180,6 +180,8 @@ struct options {
     struct addrset denyset;
     int httpserver;
     int nsock_engine;
+    /* Output messages useful for testing to stderr? */
+    int test;
 
     /* Loose source-routing stuff */
     struct in_addr srcrtes[8];

ncat/ncat_main.c

@@ -309,6 +309,7 @@ int main(int argc, char *argv[])
         {"proxy-type",      required_argument,  NULL,         0},
         {"proxy-auth",      required_argument,  NULL,         0},
         {"nsock-engine",    required_argument,  NULL,         0},
+        {"test",            no_argument,        NULL,         0},
 #ifdef HAVE_OPENSSL
         {"ssl",             no_argument,        &o.ssl,       1},
         {"ssl-cert",        required_argument,  NULL,         0},
@@ -471,6 +472,8 @@ int main(int argc, char *argv[])
                 if (nsock_set_default_engine(optarg) < 0)
                     bye("Unknown or non-available engine: %s.", optarg);
                 o.nsock_engine = 1;
+            } else if (strcmp(long_options[option_index].name, "test") == 0) {
+                o.test = 1;
             } else if (strcmp(long_options[option_index].name, "broker") == 0) {
                 o.broker = 1;
                 /* --broker implies --listen. */