Man pages are a common way to learn the commands that are on your system. The man command will give you all the details of a given command, including switches used, and syntax. man formats and displays the on-line manual pages. This post will show the quick steps to install man command on linux CentOS 5.7 server.
[root@CentOS57 ~]# yum install man -y
[root@CentOS57 ~]# yum install man -y Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirror.oscc.org.my * extras: mirror.oscc.org.my * rpmforge: ftp-stud.fht-esslingen.de * updates: mirror.oscc.org.my Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package man.i386 0:1.6d-2.el5 set to be updated --> Processing Dependency: groff >= 1.18 for package: man --> Processing Dependency: bzip2 for package: man --> Processing Dependency: nroff-i18n for package: man --> Running transaction check ---> Package bzip2.i386 0:1.0.3-6.el5_5 set to be updated ---> Package groff.i386 0:1.18.1.1-13.el5 set to be updated --> Finished Dependency Resolution Dependencies Resolved ==================================================================================================== Package Arch Version Repository Size ==================================================================================================== Installing: man i386 1.6d-2.el5 base 262 k Installing for dependencies: bzip2 i386 1.0.3-6.el5_5 base 49 k groff i386 1.18.1.1-13.el5 base 1.9 M Transaction Summary ==================================================================================================== Install 3 Package(s) Upgrade 0 Package(s) Total download size: 2.2 M Downloading Packages: (1/3): bzip2-1.0.3-6.el5_5.i386.rpm | 49 kB 00:00 (2/3): man-1.6d-2.el5.i386.rpm | 262 kB 00:02 (3/3): groff-1.18.1.1-13.el5.i386.rpm | 1.9 MB 00:17 ---------------------------------------------------------------------------------------------------- Total 104 kB/s | 2.2 MB 00:21 Running rpm_check_debug Running Transaction Test Finished Transaction Test Transaction Test Succeeded Running Transaction Installing : bzip2 1/3 Installing : groff 2/3 Installing : man 3/3 Installed: man.i386 0:1.6d-2.el5 Dependency Installed: bzip2.i386 0:1.0.3-6.el5_5 groff.i386 0:1.18.1.1-13.el5 Complete!
To man command manual simply run “man man” as below :
[root@CentOS57 ~]# man man
man(1) man(1) NAME man - format and display the on-line manual pages SYNOPSIS man [-acdfFhkKtwW] [--path] [-m system] [-p string] [-C config_file] [-M pathlist] [-P pager] [-B browser] [-H htmlpager] [-S section_list] [section] name ... DESCRIPTION man formats and displays the on-line manual pages. If you specify sec- tion, man only looks 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. OPTIONS -C config_file Specify the configuration file to use; the default is /etc/man.config. (See man.config(5).) -M path Specify the list of directories to search for man pages. Sepa- rate 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 vari- able. By default, man uses /usr/bin/less -is. -B Specify which browser to use on HTML files. This option over- rides the BROWSER environment variable. By default, man uses /usr/bin/less-is, -H Specify a command that renders HTML files as text. This option overrides the HTMLPAGER environment variable. By default, man uses /bin/cat, -S section_list List is a colon separated list of manual sections to search. This option overrides the MANSECT environment variable. -a By default, man will exit after displaying the first manual page it finds. Using this option forces man to display all the man- ual pages that match name, not just the first. -c Reformat the source man page, even when an up-to-date cat page exists. This can be meaningful if the cat page was formatted for a screen with a different number of columns, or if the pre- formatted page is corrupted. -d Donât actually display the man pages, but do print gobs of debugging information. -D Both display and print debugging info. -f Equivalent to whatis. -F or --preformat Format only - do not display. -h Print a help message and exit. -k Equivalent to apropos. -K Search for the specified string in *all* man pages. Warning: this is probably very slow! It helps to specify a section. (Just to give a rough idea, on my machine this takes about a minute per 500 man pages.) -m system Specify an alternate set of man pages to search based on the system name given. -p string Specify the sequence of preprocessors to run before nroff or troff. Not all installations will have a full set of preproces- sors. Some of the preprocessors and the letters used to desig- nate them are: eqn (e), grap (g), pic (p), tbl (t), vgrind (v), refer (r). This option overrides the MANROFFSEQ environment variable. -t Use /usr/bin/groff -Tps -mandoc to format the manual page, pass- ing the output to stdout. The default output format of /usr/bin/groff -Tps -mandoc is Postscript, refer to the manual page of /usr/bin/groff -Tps -mandoc for ways to pick an alter- nate format. Depending on the selected format and the availability of printing devices, the output may need to be passed through some filter or another before being printed. -w or --path Donât actually display the man pages, but do print the loca- tion(s) of the files that would be formatted or displayed. If no argument is given: display (on stdout) the list of directories that is searched by man for man pages. If manpath is a link to man, then "manpath" is equivalent to "man --path". -W Like -w, but print file names one per line, without additional information. This is useful in shell commands like man -aW man | xargs ls -l