Index: usr.bin/top/screen.c
===================================================================
--- usr.bin/top/screen.c
+++ usr.bin/top/screen.c
@@ -55,7 +55,8 @@
 static char is_a_terminal = false;

 #define NON_INTERACTIVE_MODE_VIRTUAL_SCREEN_WIDTH 1024
+#define DUMB_TERMINAL_SCREEN_WIDTH 80

 void
 init_termcap(bool interactive)
 {
@@ -86,9 +87,10 @@
     if (term_name == NULL)
     {
 	smart_terminal = false;
+	screen_width = DUMB_TERMINAL_SCREEN_WIDTH - 1;
 	return;
     }

     /* now get the termcap entry */
     if ((status = tgetent(termcap_buf, term_name)) != 1)
     {
@@ -124,25 +126,25 @@
     /* screen_width is a little different */
     if ((screen_width = tgetnum("co")) == -1)
     {
-	screen_width = 79;
+	screen_width = DUMB_TERMINAL_SCREEN_WIDTH - 1;
     }
     else
     {
 	screen_width -= 1;
     }

     /* terminals that overstrike need special attention */
     overstrike = tgetflag("os");

     /* initialize the pointer into the termcap string buffer */
     bufptr = string_buffer;

     /* get "ce", clear to end */
     if (!overstrike)
     {
 		clear_line = tgetstr("ce", &bufptr);
     }

     /* get necessary capabilities */
     if ((clear_screen  = tgetstr("cl", &bufptr)) == NULL ||
 	(cursor_motion = tgetstr("cm", &bufptr)) == NULL)