====== Locate Read And Use System Documentation Including Man Info And Files In Usr Share Doc ======

**General Information**

Using various documentation sources. 

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===== man pages =====

Index man page database
<code bash>
mandb
</code>
  * This is required for search results to be returned correctly (if it has not been done)
  * This command replaces the "makewhatis" command in RHEL 4/5/6.

\\
Search man page title and description only
<code bash>
man -k vim
</code>

\\
Search man page documentation for keyword (title, description, and pages)
<code bash>
apropos passwd
</code>

\\
Open specific man page section
<code bash>
man 5 passwd
</code>
  * Opens section 5 of the passwd man pages

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===== info utility =====

  * info pages => Texinfo GNU documentation
  * Organized like an FTP directory web page (links to other pages, going up/down the hierarchy, etc)
  * Searches /usr/share/info/
  * If no info pages, it opens up the man page
  * A "Node" = the page
  * ? => to see command keys for info
    * Arrow Up => Up one line
    * Arrow Down => Down one line
    * Tab => Next hyperlink
    * Return => Follow hyperlink
    * l => Go back to the last/previous node
    * Space => One screenful forward
    * Delete => One screenful backward
    * s => Search for a pattern
    * } => Next pattern match
    * { => Previous pattern match
    * n => next node on this level
    * p => previous node on this level
    * u => up one level
  * Two commands:
    * info = original command
    * pinfo = menu items are clearly indicated (use this one)

Search Info Pages for "tee"
<code bash>
pinfo --apropos tee

"(coreutils)tee invocation" -- tee
</code>

\\
Open the tee section of coreutils
<code bash>
pinfo coreutils tee
</code>

----

===== Other locations for documentation =====

Documentation store for installed programs
  * /usr/share/doc

Search system for keywords
<code bash>
updatedb
locate passwd
</code>
  * updatedb => updates the search index, usually done via cron

\\
Show location of binary
<code bash>
which passwd
</code>

\\
Search man page descriptions only
<code bash>
whatis passwd
</code>

\\
Find binary, source files, config files, and man page locations
<code bash>
whereis passwd
</code>

\\
Search documenation installed
<code bash>
rpm -qd packagename
</code>
  * Only if installed via a rpm package (either via rpm or yum)

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===== Finding Files With Locate And Find =====

==== Locate ====

Search cache database for patterns, very fast, but simple pattern searching.

Install package
<code bash>
yum install mlocate
</code>

\\
Update cache database
<code bash>
updatedb
</code>

\\
Find files/folders called "syslog"
<code bash>
locate syslog
</code>

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==== Find ====

Real time searching. Slower, but more flexible.

Find files/directories with motd in the name
<code bash>
find / -name motd
</code>

\\
Find, starting in /, all files (type f) owned by rjones
<code bash>
find / -user rjones -type f
</code>

\\
Remove all files owned by rjones
<code bash>
find / -user rjones -type f -exec rm '{}' \;
</code>

\\
Find all files modified in the last 3 days
<code bash>
find / -mtime -3 -type f
</code>

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