An awk program is mostly composed of rules, each consisting of a
pattern followed by an action. The action is enclosed in `{' and
`}'. Either the pattern may be missing, or the action may be
missing, but not both. If the pattern is missing, the
action is executed for every input record. A missing action is
equivalent to `{ print }', which prints the entire line.
Comments begin with the `#' character, and continue until the end of the
line. Blank lines may be used to separate statements. Statements normally
end with a newline; however, this is not the case for lines ending in a
`,', `{', `?', `:', `&&', or `||'. Lines
ending in do or else also have their statements automatically
continued on the following line. In other cases, a line can be continued by
ending it with a `\', in which case the newline is ignored.
Multiple statements may be put on one line by separating each one with a `;'. This applies to both the statements within the action part of a rule (the usual case), and to the rule statements.
See section Comments in awk Programs, for information on
awk's commenting convention;
see section awk Statements Versus Lines, for a
description of the line continuation mechanism in awk.
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