Section 1.
Getting Help.
"The Linux
philosophy is ’laugh in the face of danger’.
Oops. Wrong one. ’Do it yourself’.
That’s it."
Linus Torvald 1996.
1. Getting help.
The main options for obtaining
help are the man pages, infotext, built in
command help and web pages.
1.1. Tools:
man, info, apropos, whereis,
whatis.
bash-4.2$ man -f man
man [] (1) - format and display the on-line manual pages
man [] (7) - pages - conventions for writing Linux man pages
man.conf [] (5) - configuration data for man
man [] (1) - format and display the on-line manual pages
man [] (7) - pages - conventions for writing Linux man pages
man.conf [] (5) - configuration data for man
man [] (1) - format and display the on-line manual pages
man [] (7) - macros to format man pages
man [] (7) - pages - conventions for writing Linux man pages
man.conf [] (5) - configuration data for man
bash-4.2$ man man
man 1 September 19,
2005
NAME man − format
and display the on-line manual pages
SYNOPSIS man name
...
DESCRIPTION man formats
and displays the on-line manual pages. If you specify
section, man looks only in that section of the
manual. name is normally the name of the manual page,
which is typically the name of a command, function, or file.
However, if name contains a slash then man
interprets it as a file specification, so that you can do
man ./foo.5 or even man /cd/foo/bar.1.gz.
See below for a description of
where man looks for the manual page files.
MANUAL SECTIONS The
standard sections of the manual include:
1 User
Commands
2 System
Calls
3 C
Library Functions
4
Devices and Special Files
5 File
Formats and Conventions
6 Games
et. Al.
7
Miscellanea
8 System
Administration tools and Daemons
Distributors customise the
manual section to their specifics, which often include
additional sections.
OPTIONS
−C
config_file Specify the configuration file to use; the
default may be based)/usr/lib/man.conf(Debian
/etc/man.config (Red Hat, CentOS et al) or
/usr/lib64/man.conf (Slackware).
(See man.conf (5).)
−M
path Specify the list of directories to search for man
pages. Separate the directories with colons. An empty list
is the same as not specifying −M at all. See
SEARCH PATH FOR MANUAL PAGES.
−P
pager Specify which pager to use. This option overrides the
MANPAGER environment variable, which in turn
overrides the PAGER variable. By default, man
uses /usr/bin/less -is.
−B
Specify which browser to use on HTML files. This option
overrides the BROWSER environment variable. By
default, man uses /usr/bin/lynx,
−H
Specify a command that renders HTML files as text. This
option overrides the HTMLPAGER environment variable.
By default, man uses /usr/bin/lynx -dump.
Linux Man pages - Frederico Lucifredi et al. (truncated and
edited)
Every systems administrator
should be able to write simple man pages in support of their
administration tools. See the chapter on nroff and
troff to learn more on how to do this.
1.2. Built in help.
Many commands have some built in
help text. Using commands with the options "-h",
"--help" or "-?" will often produce
limited help.
1.3. Web pages
There is extensive help
available on the web. Search on any Linux command and you
will almost certainly find a wealth of material on line
including the man pages. The Ubuntu web pages have
been, for the most part, quite beautifully prepared for use
in a web browser. If you have internet access and a web
browser available using "ubunto man <command
name>" will bring forth the man pages in a form much
more readily navigated than that managed in a terminal
window.
1.4. Exercises.
Try the following:
sa101$ man -f man
sa101$ man apropos
sa101$ apropos man
sa101$ info
sa101$ info info
sa101$ info man
sa101$ whatis man
sa101$ whereis man
sa101$ man whereis
sa101$ whereis -m man
sa101$ man passwd
sa101$ man 5 passwd
sa101$ man useradd
Try using "man info"
in a search engine.
Who is the current maintainer of
"man"?
What does the -P option allow
you to do?
Examine the man.conf
file.
Experiment with the tools listed
in the table below.
1.5. Tools:
