Clear Screen

When you need to clear your screen, just issue proper command in your shell. cmd, bash, PowerShell, or dozens of other console applications have either clear or cls. Moreover, many of them respond to Ctrl+L hotkey.

It doesn’t matter are you working in ConEmu or any other terminal, your shell behavior is the same.

‘Clear’ command in the ConEmu menu

There are requests from our users to add ‘Clear’ command to the ConEmu system menu.

References: gh-550, gh-372, gh-234.

These requests were rejects by a simple and logical reason - ConEmu (terminal) do not know what console application is doing. ConEmu able to show application output, but that is all.

However, since GuiMacro Write was implemented, anyone may create a macro to Write("\ec"), which actually resets the terminal. So, anyone may choose desired hotkey for action ‘Reset terminal: clear screen, backscroll, move cursor to the upper-left corner’.

BTW, Write may be used to push to console several colored lines using ANSI sequences to ‘mark’ some point in real-time logs (tail -f). Example.

Write "\n\n\e[91m========== '\e]9;8;\"time\"\e\\' ==========\e[m\n\n"

Injurious operation

Terminal reset may harm normal behavior of running console applications. So, use it carefully and on your own risk!

Reason 1

You are editing file in vim, manage your files with Far Manager, or do something else not related to simple ‘read-line-execute-command’, and call this mysterious ‘clear’ menu item. What would happen?

Your screen would be garbaged.

Console app is sure that cursor is located in certain position and all visible lines of text file were printed properly. But after such ‘external clear’ this would not be true.

Reason 2

Even with cmd or bash. They have printed PROMPT. But after ‘external clear’ there would be no PROMPT! The screen would be absolutely clean, but shell do not know that it must ‘reprint’ PROMPT. It just waits for user input!

Reason 3

One may say: users know when they want to clear screen in appropriate moment. Yep. But that would case garbaged output due to abovementioned reasons.

Reason 4

Not related to the terminals, but it may serve as obvious example.

Imagine, that Windows would have a hotkey to Clear The Monitor. What shall it do? Fill screen with black color. And how do you think running applications and Windows would look after that? Garbage, rubbish and more.

Reason 5

In the Issue 550 I been noted about ‘example’ of the feature implementation in the Tera Term.

Well, I have tried both local cygwin connection and remote ssh to Ubuntu in the Tera Term, and it just doesn’t work.

  • Connect (to cygwin or remote via ssh)
  • Execute ls
  • Call menu item ‘Reset terminal’
  • Get fail
    • Cursor jumps to the {0,0} and that’s all!
    • Screen is not cleared!
    • Prompt is not re-printed!

Resume

To clear your screen do one of the following:

  • Issue clear or cls in your shell.
  • Press Ctrl+L or other hotkey, if your shell supports it. Even cmd+clink may do that.
  • Restart your tab. Default hotkey is Win+~.
  • (Use very carefully) Set hotkey for action ‘Reset terminal: clear screen, backscroll, move cursor to the upper-left corner’.