diff --git a/lib/widget.js b/lib/widget.js
index 54c30f9..9abcf45 100644
--- a/lib/widget.js
+++ b/lib/widget.js
@@ -8962,7 +8962,7 @@ Image.prototype.renderImage = function(img, ratio, callback) {
   var self = this;
 
   if (cp.execSync) {
-    callback = callback || function() {};
+    callback = callback || function(err, result) { return result; };
     try {
       return callback(null, this.renderImageSync(img, ratio));
     } catch (e) {
@@ -9031,7 +9031,7 @@ Image.prototype.clearImage = function(callback) {
   var self = this;
 
   if (cp.execSync) {
-    callback = callback || function() {};
+    callback = callback || function(err, result) { return result; };
     try {
       return callback(null, this.clearImageSync());
     } catch (e) {
@@ -9094,7 +9094,7 @@ Image.prototype.imageSize = function(callback) {
   var img = this.file;
 
   if (cp.execSync) {
-    callback = callback || function() {};
+    callback = callback || function(err, result) { return result; };
     try {
       return callback(null, this.imageSizeSync());
     } catch (e) {
@@ -9153,7 +9153,7 @@ Image.prototype.termSize = function(callback) {
   var self = this;
 
   if (cp.execSync) {
-    callback = callback || function() {};
+    callback = callback || function(err, result) { return result; };
     try {
       return callback(null, this.termSizeSync());
     } catch (e) {
@@ -9212,7 +9212,7 @@ Image.prototype.getPixelRatio = function(callback) {
   var self = this;
 
   if (cp.execSync) {
-    callback = callback || function() {};
+    callback = callback || function(err, result) { return result; };
     try {
       return callback(null, this.getPixelRatioSync());
     } catch (e) {
@@ -9394,6 +9394,7 @@ Image.prototype.termSizeSync = function(_, recurse) {
   if (!buf.trim()) {
     // Bug: w3mimgdisplay will sometimes
     // output nothing. Try again:
+    recurse = recurse || 0;
     if (++recurse === 5) {
       throw new Error('Term size not determined.');
     }