virsh-interface: Update interface commands to use vshCommandOptStringReq

tools/virsh-interface.c

@@ -51,7 +51,7 @@ vshCommandOptInterfaceBy(vshControl *ctl, const vshCmd *cmd,
     if (!vshCmdHasOption(ctl, cmd, optname))
         return NULL;
 
-    if (vshCommandOptString(cmd, optname, &n) <= 0)
+    if (vshCommandOptStringReq(ctl, cmd, optname, &n) < 0)
         return NULL;
 
     vshDebug(ctl, VSH_ERR_INFO, "%s: found option <%s>: %s\n",
@@ -503,7 +503,7 @@ cmdInterfaceDefine(vshControl *ctl, const vshCmd *cmd)
     bool ret = true;
     char *buffer;
 
-    if (vshCommandOptString(cmd, "file", &from) <= 0)
+    if (vshCommandOptStringReq(ctl, cmd, "file", &from) < 0)
         return false;
 
     if (virFileReadAll(from, VSH_MAX_XML_FILE, &buffer) < 0)
@@ -778,10 +778,8 @@ cmdInterfaceBridge(vshControl *ctl, const vshCmd *cmd)
     }
 
     /* Name for new bridge device */
-    if (vshCommandOptString(cmd, "bridge", &br_name) <= 0) {
-        vshError(ctl, "%s", _("Missing bridge device name in command"));
+    if (vshCommandOptStringReq(ctl, cmd, "bridge", &br_name) < 0)
         goto cleanup;
-    }
 
     /* make sure "new" device doesn't already exist */
     if ((br_handle = virInterfaceLookupByName(ctl->conn, br_name))) {