resolve discussion about param[out] and return value

src/auxiliary.c

@@ -195,13 +195,14 @@ int parse_int(const char * input, int * result)
 /**
  * Add the SSH_COMMAND string in front of ssh_key unless it's already there
  * because people have seen it being used in ssh_keys_list.
- * @param[in]   ssh_key a valid ssh key string
+ * @param[out]  ssh_key_with_command    the ssh_key with the command prepended
+ *                                      if needed
+ * @param[in]   ssh_key                 a valid ssh key string
  */
 int add_ssh_command(char ** ssh_key_with_command, const char * ssh_key)
 {
     if(strncmp(SSH_COMMAND, ssh_key, strlen(SSH_COMMAND)) != 0)
-        asprintf(ssh_key_with_command, "%s %s", SSH_COMMAND, ssh_key);
+        return asprintf(ssh_key_with_command, "%s %s", SSH_COMMAND, ssh_key);
     else
-        asprintf(ssh_key_with_command, "%s", ssh_key);
-    return 0;
+        return asprintf(ssh_key_with_command, "%s", ssh_key);
 }