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Getting Started with `awk'
**************************

   The basic function of `awk' is to search files for lines (or other
units of text) that contain certain patterns.  When a line matches one
of the patterns, `awk' performs specified actions on that line.  `awk'
keeps processing input lines in this way until the end of the input
file is reached.

   When you run `awk', you specify an `awk' "program" which tells `awk'
what to do.  The program consists of a series of "rules".  (It may also
contain "function definitions", but that is an advanced feature, so we
will ignore it for now.  User-defined)
Each rule specifies one pattern to search for, and one action to
perform when that pattern is found.

   Syntactically, a rule consists of a pattern followed by an action.
The action is enclosed in curly braces to separate it from the pattern.
Rules are usually separated by newlines.  Therefore, an `awk' program
looks like this:

     PATTERN { ACTION }
     PATTERN { ACTION }
     ...

* Menu:

* Very Simple                  A very simple example.
* Two Rules                    A less simple one-line example with two rules.
* More Complex                 A more complex example.
* Running gawk                 How to run `gawk' programs;
                                includes command line syntax.
* Comments                     Adding documentation to `gawk' programs.
* Statements/Lines             Subdividing or combining statements into lines.
* When                         When to use `gawk' and
                                when to use other things.