get unix socket path from argv

main.c

@@ -14,8 +14,6 @@
 #define BACKLOG 10
 #define DIE(info) ({perror((info)); exit(EXIT_FAILURE);})
 
-static const char *socket_path = "/tmp/plumb-unix0";
-
 struct client {
     int fd;
 };
@@ -175,7 +173,7 @@ void server_free(struct server *s)
     free(s);
 }
 
-struct server *server_create()
+struct server *server_create(const char *socket_path)
 {
     struct server *s = malloc(sizeof(struct server));
     if (s == NULL) {
@@ -195,6 +193,8 @@ struct server *server_create()
     name.sun_family = AF_UNIX;
     strncpy(name.sun_path, socket_path, sizeof(name.sun_path) - 1);
 
+    unlink(socket_path);
+
     if (bind(s->sock_fd, (const struct sockaddr *)&name, sizeof(name)) == -1) {
         free(s);
         close(s->sock_fd);
@@ -300,14 +300,32 @@ int server_turn(struct server *s)
     return 0;
 }
 
-int main()
+
+const char *arg_shift(int *argc, char ***argv) {
+    if (*argc < 1)
+        return NULL;
+
+    const char *result = *argv[0];
+    *argc -= 1;
+    *argv += 1;
+    return result;
+}
+
+int main(int argc, char *argv[])
 {
-    struct server *srv = server_create();
+    arg_shift(&argc, &argv);
+
+    const char *socket_path = arg_shift(&argc, &argv);
+    socket_path = socket_path == NULL ? "/tmp/duct-unix0" : socket_path;
+
+    struct server *srv = server_create(socket_path);
     if (srv == NULL) {
         fprintf(stderr, "server_create failed\n");
         return EXIT_FAILURE;
     }
 
+    printf("Listening on %s\n", socket_path);
+
     while (1) {
         if (server_turn(srv) < 0) {
             fprintf(stderr, "server_turn failed\n");