Operators

The shell uses arithmetic operators from the C programming language; the following table lists the operators in decreasing order of precedence.

Operator

Description

++ --

Auto-increment and auto-decrement, both prefix and postfix.

+ - ! ˜

Unary plus and minus, logical negation and binary inversion (one’s complement).

**

Exponentiation.

* / %

Multiplication; division; modulus (remainder).

+ -

Addition; subtraction.

<< >>

Bitwise left shift; bitwise right shift.

< <= > >=

Less than; less than or equal to; greater than; greater than or equal to.

== !=

Equality; inequality (both evaluated left to right).

&

Bitwise AND.

^

Bitwise exclusive OR.

|

Bitwise OR.

&&

Logical AND (short-circuit).

||

Logical OR (short-circuit).

?:

Inline conditional evaluation.

= += -=

Assignment.

*= /= %=

 

< <= > >=

 

&= ^= |=

 

'

Sequential expression evaluation.

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