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Linux Pocket Guide, 2nd Edition by Daniel J. Barrett

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Getting Help

If you need more information than this book provides, there are several things you can do.

Run the man command

The man command displays an online manual page, or manpage, for a given program. For example, to learn about listing files with ls, run:

$ man ls

To search for manpages by keyword for a particular topic, use the -k option followed by the keyword:

$ man -k database
Run the info command

The info command is an extended, hypertext help system covering many Linux programs.

$ info ls

While info is running, some useful keystrokes are:

  • To get help, type h

  • To quit, type q

  • To page forward and backward, use the space bar and Backspace keys

  • To jump between hyperlinks, press TAB

  • To follow a hyperlink, press Enter

If info has no documentation on a given program, it displays the program’s manpage. For a listing of available documentation, type info by itself. To learn how to navigate the info system, type info info.

Use the --help option (if any)

Many Linux commands respond to the option --help by printing a short help message. Try:

$ ls --help

If the output is longer than the screen, pipe it into the less program to display it in pages (press q to quit):

$ ls --help | less
Examine the directory /usr/share/doc

This directory contains supporting documents for many programs, usually organized by program name and version. For example, files for the text editor emacs, version 23, are likely found (depending on distro) in /usr/share/doc/emacs23.

GNOME and KDE Help

For help with GNOME or KDE, ...

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