Terminal Activity

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Activity-terminal.svg The Terminal activity grants access to the XO's Linux command line.

The Terminal is an Activity that allows you to control your XO directly from a command line, similar to the Terminal program in Mac OS X or the Command Prompt in Microsoft Windows. The Terminal allows you to do far more with your XO than running Sugar activities. But BEWARE it is also possible to delete your data, so be careful. And if you become the root user, you have full control of the computer and can destroy all software!

See the Terminal manual.

Starting Terminal

The Terminal Activity is usually not marked as a favorite, so it does not appear in the Home View Favorites view.

In the Home View, press ctrl-2 to select the List view, search for Terminal, and click on it to start.

You might also mark it as a favorite if you like.

Starting a console

You can also access a Linux command prompt by switching to the console, instead of starting the Terminal activity.

Common Terminal commands

When you start Terminal, it runs the Bash "shell" program that interprets keystrokes and commands. Its main job is to allow you to run other programs, for example:

  • nano for editing text files directly. If you want to edit text files in Sugar, use Write.
  • yum for automatically installing new software.
  • rpm - another way to automatically install new software
  • olpc-logbat - log the activity of the battery system. Useful for assisting developers in debugging battery problems.

There are hundreds of Linux commands available in the Terminal, Linux software describes some more of them. The OLPC system software on the XO is a slimmed-down version of Fedora and so its command-line programs come from Fedora. Many command-line programs from Fedora are not available but experienced users can add them using yum or rpm.

Users and super-user

Initially Terminal begins as the default user (usually "olpc"). Some programs require that you run them as the root "super-user. You can prepend sudo to some of these, or press the #_ icon in the Activity menu to become root, or enter su -l to become root. The root user has awesome destructive power, do not run commands as root unless you have to.

Copy and paste in Terminal

  • Use the Edit menu

Where is the Edit menu?

  • Press Shift+Ctrl+C to copy, Shift+Ctrl+V to paste. (You have to hold the shift key down in addition because Ctrl+C and Ctrl+V are meaningful key combinations in terminal programs.)
  • Plug a three-button mouse into a USB port and use the middle mouse button to paste.
  • Click both buttons below the XO-1's track pad (or click directly between them) to paste.

You can select text in Terminal's window and use the last technique to duplicate it without first copying it to the Sugar clipboard.

Other keystroke commands

Keyboard shortcuts lists special keys in Sugar. Some of these don't work in Terminal, or require that you press the Shift key as well.

Change font size in the Terminal activity

To increase the print size in Terminal:

  • Launch the Terminal activity.
  • Type
nano ~/.sugar/default/terminalrc
  • Find the line saying
Font = Monospace

And change it to

Font = Monospace 16

(or whatever you want—see Fonts for info on determining available fonts).

  • Press Control+X and answer Yes to save.
  • Stop the Terminal activity (the stop-sign icon in the top right-hand corner of the Activity menu)
  • Re-open Terminal, the terminal should now be in a larger font.

CAUTION: When you change to a larger font as described, you may find that the text continues on following lines or wraps around in a confusing fashion. This is particularly true if you try to use the nano editor to make further changes. In that case you may have to use the vi editor which also is supplied with the terminal activity (type:

vi ~/.sugar/default/terminalrc

Be sure you understand how the vi editor works. If you make an error in saving the changes, you may render the terminal inoperative. The only way to restore it then may be to do a reinstall of sugar from a USB drive. (this is the writer's experience).

The Console

Another way to bring up the Linux command prompt is by pressing the Ctrl+Alt+F2 keys in sequence.

By design, not all XOs have the F2 legend on the key, see Keyboard#Missing_keys.

Ctrl-Alt-F2 will switch to a console terminal that runs outside the Sugar and GNOME.

To return to the Sugar or GNOME environment, press Alt+F1. (On releases before 11.2.0, use Alt+F3).

Most Sugar or GNOME commands won't work on the console.

Logging in

Press enter, and the console will log you in as root. (On some older releases, you may see a login prompt, if so type root and press enter.)

You are now logged in as the root user, be very careful.

Alternative terminal program

You can install gnome-terminal:

su -l
yum install gnome-terminal

Here are the changes proposed:

After you press return you may receive a number of lines of text which end with "error 404 Not Found Trying other mirror".

Be Patient: Eventually you should see a download of 4.4 MB then on the next line fedora

then you will see

primary.squlite.bz 2 6.1MB

When you receive a -bash-3.2# prompt the load is complete.

End of change so far:

Use an existing terminal session to launch a 'gnome-terminal' session.

COMMENT:

Here there should be additional guidance. What is done next is not clear. The natural thing to do would be to exit the root into for the normal terminal prompt

Then enter "gnome" or "gnome-terminal" .

However neither command yields anything but "bash: gnome-terminal (or gnome): command not found.

So that is all i can contribute at this time. LUDD.

See also

  • Linux software A brief description of some of the linux software that is installed with Sugar.
  • BASH Reference A longer list of commands and programs (many are not installed on the XO-1 by default due to its constrained storage).