Manual Pages (man)

Use: Use the man command when you know the command name, but are unsure about the syntax of the command.

The University system has manual pages available through the terminal window. These pages contain documentation on the UNIX commands, including how they are executed, associated options, and what the command does.

man input:

eos$ man commandname

If you receive “No manual entry found for commandname”, it means that the command you typed is not recognized on the NC State system.

To advance in the document, use the UP and DOWN arrow keys, use Q to exit the manual.

How to read a manual page

Below is a typical manual page. The amount of information presented in the pages depends on the command that you are looking up.

GREP(1)                                                                GREP(1)



NAME
       grep, egrep, fgrep - print lines matching a pattern

SYNOPSIS
       grep [OPTIONS] PATTERN [FILE...]
       grep [OPTIONS] [-e PATTERN | -f FILE] [FILE...]

DESCRIPTION
       grep  searches the named input FILEs (or standard input if no files are
       named, or if a single hyphen-minus (-) is given as file name) for lines
       containing  a  match to the given PATTERN.  By default, grep prints the
       matching lines.

       In addition, two variant programs egrep and fgrep are available.  egrep
       is  the  same  as  grep -E.   fgrep  is  the  same  as grep -F.  Direct
       invocation as either egrep or fgrep is deprecated, but is  provided  to
       allow historical applications that rely on them to run unmodified.

OPTIONS
   Generic Program Information
       --help Print  a  usage  message  briefly summarizing these command-line
              options and the bug-reporting address, then exit.

:

Figure 1: Part of the manual page for grep

The SYNOPSIS section gives an overview of the syntax of the command. Underlined words are parameters where arguments, such as the file name, go. [Bracketed] words are optional. DO NOT use brackets when executing the command.

Note that in some cases the order of the arguments is significant.

Should I expect an output?

Yes. The contents of the man page should be displayed on the screen.

Can I search the man pages?

Yes. You can use the following command to search all the manual pages for keywords: apropos.

syntax: apropos keywords

Example

eos$ apropos directory

A single line will then display in the terminal window for each man page that contains the word “directory”.