second commit

tools/erase_lines

@@ -0,0 +1,42 @@
+#!/bin/bash
+
+# Clears the entire current line regardless of terminal size.
+# See the magic by running:
+# { sleep 1; clear_this_line ; }&
+clear_this_line(){
+        printf '\r'
+        cols="$(tput cols)"
+        for i in $(seq "$cols"); do
+                printf ' '
+        done
+        printf '\r'
+}
+
+# Erases the amount of lines specified.
+# Usage: erase_lines [AMOUNT]
+# See the magic by running:
+# { sleep 1; erase_lines 2; }&
+erase_lines(){
+        # Default line count to 1.
+        test -z "$1" && lines="1" || lines="$1"
+
+        # This is what we use to move the cursor to previous lines.
+        UP='\033[1A'
+
+        # Exit if erase count is zero.
+        [ "$lines" = 0 ] && return
+
+        # Erase.
+        if [ "$lines" = 1 ]; then
+                clear_this_line
+        else
+                lines=$((lines-1))
+                clear_this_line
+                for i in $(seq "$lines"); do
+                        printf "$UP"
+                        clear_this_line
+                done
+        fi
+}
+
+erase_lines "$1"