Linux clear all screen

How to clear screen in linux

Solution 1: Some terminals, such as xterm, support what is known as an “alternate screen”: there are separate screens for full-screen programs and for scrolling programs. I want to reset completely the terminal buffer (i.e. I don’t want to scroll down or add newlines to clear the screen), without using curses/ncurses please (I don’t like the ncurses screen mode, I want to stick with the default mode).

Clearing GNU Screen after full-screen application

When working at a normal xterm (not sure about a «real» terminal), when a full- screen program such as man or vim is closed, it disappears, leaving your screen so you can see your prompt, and previous prompts including where you launched the program that closed.

When I am running within GNU Screen, however, when the program is closed it does not clear but is simply shifted up so a prompt can be displayed. To me this is ****, and I’d like to know if «normal» behaviour can be resumed.

I realise I could manually clear the screen myself but a) I don’t want to and b) that would result in a totally clear screen, not what I’m after (though perhaps better, if this is as good as it gets).

Some terminals, such as xterm, support what is known as an “alternate screen”: there are separate screens for full- screen programs and for scrolling programs. In xterm, you can switch between the two screens with the “show alternate screen” command at the bottom of the Ctrl + mouse 2 menu.

This behavior is disabled by default in screen but can be enabled with the altscreen option: add altscreen on to your ~/.screenrc .

This is related to your termcap settings for screen. Maybe you can try starting screen with the -a command line option.

Linux — How to clear screen on protected mode, 1 Answer. You can write \x1b [2J to the standard output so the terminal get cleared and fix the cursor position using \x1b [H, for example in nasm: global _start section .data clr db 0x1b, » [2J», 0x1b, » [H» clrlen equ $ — clr section .text _start: mov eax, 4 mov ebx, 1 mov ecx, clr mov edx, clrlen int 0x80 mov eax, …

How can I remove the clear screen before login

On ubuntu server , how can I avoid the screen being cleared just before the login screen pops?

I’m trying to read an error message on one of the services and I get this annoying clear screen and I cannot scroll up with shift-pageUp.

for systemd set TTYVTDisallocate to no.

to achieve this, run systemctl edit getty@tty1 and enter the code below

[Service] TTYVTDisallocate=no 

Viewing the last screen of messages that appeared during boot

When Ubuntu Server boots, the messages you see are typically written to tty7 (the seventh virtual console). When booting completes , you are switched to tty1, where you are prompted to log on. Thus, the boot messages are not actually cleared; you are simply switched to a different console from the one that contains them.

To view them again, you can switch to tty7 by pressing Alt+F7. You can switch back to tty1 with Alt+F1 (and to the second with Alt+F2, and so forth). This does not (and should not) apply on most Ubuntu Server systems, but when a GUI is running, Ctrl+Alt+F1 must be used to switch to tty1 (and Ctrl+Alt+F2 for tty2, and so forth).

Preventing the screen from being cleared after a user logs out, so the text from their session is visible in the subsequent session

In your home directory there is a file called .bash_logout which contains something like:

if [ "$SHLVL" = 1 ]; then [ -x /usr/bin/clear_console ] && /usr/bin/clear_console -q fi

That is what causes the screen to be cleared on logout. To stop that from happening, comment out all those lines, so it looks like:

#if [ "$SHLVL" = 1 ]; then # [ -x /usr/bin/clear_console ] && /usr/bin/clear_console -q #fi

After hours of googling, I found the solution in this thread and this question.

First, add console=tty1 to your GRUB_CMDLINE_LINUX (I also suggest to add noplymouth to inhibit plymouth and its useless splashscreen).

#> sudo vi /etc/default/grub GRUB_CMDLINE_LINUX="console=tty1 noplymouth" 

This forces the kernel log to be printed on tty1 instead of tty7 and avoid the tty switch before the login prompt.

Then just go into /etc/init and edit one or more of tty1.conf , tty2.conf , tty3.conf , tty4.conf , tty5.conf , tty6.conf or console.conf . I edited them all adding —noclear option to the getty command. For example, editing tty1.conf :

respawn exec /sbin/getty -8 38400 tty1 

respawn exec /sbin/getty -8 38400 --noclear tty1 

That’s all, run sudo update-grub and now your system should boot in a single tty without clearing it.

How to FULLY clear terminal screen?, 1 Answer. Sorted by: 2. The command prompt format is stored in the PS1 environment variable. If you set it to the empty string, no command prompt will be displayed. You can then clear the console: user@host:$ PS1= clear. If you need to restore it afterwards, you can save the initial value in a different variable first: …

How can you clear (reset) the screen in unix/posix? (not curses/newlines)

I’d like to know (if it’s possible) how can you clear/reset the terminal screen in linux/mac/unix (not DOS) like you would do on windows/DOS with clrscr () from «conio.h». I know there are similar questions here and on the web in general, but I wasn’t able to find one that answered my particular case.

ATTENTION: I know about curses/ncurses and solutions that emulate system(«clear») but that’s not what I want. I want to reset completely the terminal buffer (i.e. I don’t want to scroll down or add newlines to clear the screen), without using curses/ncurses please (I don’t like the ncurses screen mode, I want to stick with the default mode).

Is it possible or I’m asking something impossible? 😛 I’m trying to make a console-game (not exactly a roguelike) without curses, and I don’t like to see what I printed on the screen before clearing it just by scrolling up.

EDIT: I’ve tried system(«reset»), that’s not a nice way using a system call, and it’s getting a bad delay using that command but it’s close to what I want to do.. Is there some kind of function/library that can do something similar?

I think that’ll be a good solution as well to do something like move(0,0) and then print again what I need or just blank space (this way I won’t have scrolling and the old text above it). But I don’t know if there’s a library that will do that without going un curses mode.

For now see my own answer below, I’m using

this is working fine for now and solved my problem. If anybody knows any issue with this solution please let me know. I have an issue with the cursor visibility. If it was hidden this code will show it again, do you know a fix for this?

I’ve just discovered thanks to Jayesh that this escape code will clear my screen correctly , thanks!

EDIT: need fix! This will set the cursor visible if it was hidden previously.. How do I get the same thing without changing the cursor visibility?

If anybody will point out any issue about portability on posix/unix (linux/mac) systems, I will update the answer with a better solution.

For POSIX, you can use terminfo. Request the «clear» command using tigetstr and output the command using putp.

For Windows, you would be looking at using FillConsoleOutputCharacter and filling the console with spaces.

Then just abstract the two methods and you have a cross-platform mechanism.

write(STDOUT_FILENO, "\x1b[2J", 4); 

Linux — Clear Screen in «watch» Command, The watch command clears the terminal so that the output of the command is clear and there is no clutter. When another program outputs such as the echo statements in the example, the result is a little weird. It prints strangely and the results seem to depend on the size of the output. Even though watch …

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How to Clear Terminal Screen in Ubuntu and Other Linux Distributions [Beginner’s Tip]

When you are working in the terminal, often you’ll find that your terminal screen is filled up with too many commands and their outputs.

You may want to clear the terminal to declutter the screen and focus on the next task you are going to perform. Clearing the Linux terminal screen helps a lot, trust me.

Clear Linux terminal with clear command

So, how do you clear terminal in Linux? The simplest and the most common way is to use the clear command:

You need no option with the clear command. It’s that simple but there are some additional things you need to know about it.

The clear command and other methods of clearing screen may depend on the terminal emulator you are using. Terminal emulator is the terminal application that you use for accessing the Linux shell (command line).

If you use clear command on Ubuntu with GNOME Terminal, it will clear the screen and you won’t be able to see what else you had on the screen previously.

In many other terminal emulators or Putty, it may just clear the screen for one page. If you scroll with mouse or PageUp and PageDown keys, you can still access the old screen outputs.

Frankly, it depends on your need. If you suddenly realize that you need to refer to the output of a previously run command, perhaps having that option available will be helpful.

Other ways to clear terminal screen in Linux

Clear command is not the only way to clear the terminal screen.

You can use Ctrl+L keyboard shortcut in Linux to clear the screen. It works in most terminal emulators.

If you use Ctrl+L and clear command in GNOME terminal (default in Ubuntu), you’ll notice the difference between their impact. Ctrl+L moves the screen one page down giving the illusion of a clean screen but you can still access the command output history by scrolling up.

Some other terminal emulators have this keyboard shortcut set at Ctrl+Shift+K.

You can also use reset command for clearing the terminal screen. Actually, this command performs a complete terminal re-initialization. It could take a bit longer than clear command, though.

There are a couple of other complicated ways to clear the screen when you want to clear the screen completely. But since the command is a bit complicated, it’s better to use it as alias in Linux:

You can add this alias to your bash profile so that it is available as command.

I know this was a pretty basic topic and most Linux users probably already knew it but it doesn’t harm in covering the elementary topics for the new Linux users. Isn’t it?

Got some secretive tip on clearing terminal screen? Why not share it with us?

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