File: gawk.info,  Node: Built-in Variables,  Next: Pattern Action Summary,  Prev: Statements,  Up: Patterns and Actions

7.5 Predefined Variables
========================

Most 'awk' variables are available to use for your own purposes; they
never change unless your program assigns values to them, and they never
affect anything unless your program examines them.  However, a few
variables in 'awk' have special built-in meanings.  'awk' examines some
of these automatically, so that they enable you to tell 'awk' how to do
certain things.  Others are set automatically by 'awk', so that they
carry information from the internal workings of 'awk' to your program.

   This minor node documents all of 'gawk''s predefined variables, most
of which are also documented in the major nodes describing their areas
of activity.

* Menu:

* User-modified::               Built-in variables that you change to control
                                'awk'.
* Auto-set::                    Built-in variables where 'awk' gives
                                you information.
* ARGC and ARGV::               Ways to use 'ARGC' and 'ARGV'.