Linux in a Nutshell, Fifth Edition

Variable and Array Assignment | 775

gawk

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Operators

The following table lists the operators, in order of increasing precedence, that are

available in awk.

While ** and **= are common extensions, they are not part of

POSIX awk.

Variable and Array Assignment

Variables can be assigned a value with an = sign. For example:

FS = ","

Expressions using the operators +, -, /, and % (modulo) can be assigned to

variables.

Arrays can be created with the split( ) function (described later), or they can

simply be named in an assignment statement. Array elements can be subscripted

with numbers (array[1],…,array[n]) or with strings. Arrays subscripted by

PROCINFO An array containing information about the process, such as real and effective UID

numbers, process ID number, and so on.

RT The text matched by RS, which can be a regular expression in gawk.

TEXTDOMAIN The text domain (application name) for internationalized messages ("messages").

Symbol Meaning

= += -= *= /= %= ^= **= Assignment.

?: C conditional expression.

|| Logical OR (short-circuit).

&& Logical AND (short-circuit).

in Array membership.

~ !~ Match regular expression and negation.

< <= > >= != == Relational operators.

(blank) Concatenation.

+ - Addition, subtraction.

* / % Multiplication, division, and modulus (remainder).

+ - ! Unary plus and minus, ...