diff -Naur fbpdf-20160804/README fbpdf-20160804.patched/README
--- fbpdf-20160804/README	2016-08-04 15:19:06.282346689 -0400
+++ fbpdf-20160804.patched/README	2016-08-04 15:07:40.384322633 -0400
@@ -22,6 +22,9 @@
 o		set page number (for 'G' command only)
 O		set page number and go to current page
 z		zoom; prefix multiplied by 10 (i.e. '15z' = 150%)
+z/=	zoom; prefix multiplied by 10 (i.e. '12z' = 120%). Default 15.
++		increase zoom by 10%
+-		decrease zoom by 10%
 r		set rotation in degrees
 i		print some information
 q		quit
diff -Naur fbpdf-20160804/fbpdf.c fbpdf-20160804.patched/fbpdf.c
--- fbpdf-20160804/fbpdf.c	2016-08-04 15:19:06.282346689 -0400
+++ fbpdf-20160804.patched/fbpdf.c	2016-08-04 15:18:38.618345719 -0400
@@ -252,6 +252,7 @@
 				srow = prow;
 			break;
 		case 'z':
+		case '=':
 			zoom_page(getcount(zoom_def));
 			break;
 		case 'w':
@@ -301,10 +302,18 @@
 		case ' ':
 		case CTRLKEY('d'):
 			srow += srows * getcount(1) - step;
+			if(srow > prows) {
+				srow = 0;
+				loadpage(num + 1);
+			}
 			break;
 		case 127:
 		case CTRLKEY('u'):
 			srow -= srows * getcount(1) - step;
+			if(srow < 0) {
+				srow = prows - step;
+				loadpage(num - 1);
+			}
 			break;
 		case '[':
 			scol = pcol;
@@ -320,6 +329,14 @@
 			break;
 		case CTRLKEY('l'):
 			break;
+		case '+':
+			count = 0;
+			zoom_page(zoom + 1);
+			break;
+		case '-':
+			count = 0;
+			if(zoom > 0) zoom_page(zoom - 1);
+			break;
 		default:	/* no need to redraw */
 			continue;
 		}