Korn Shell: Unix and Linux Programming Manual, Third Edition, The

Arithmetic Operators

The following sections contain examples for each of the arithmetic operators available to the Korn shell. Table 6.1 lists all of the arithmetic operators available to the Korn shell in order of precedence.

–expression (Unary Minus)

Evaluates to the negative value of expression.

						$ ((X=—7))
						$ ((Y=—X + 2))
						$ print — "$X $Y" 
—7 9
					

The print – command is used so that the negative sign is not interpreted as an argument.

!expression (Logical Negation)

The ! operator returns 0 (true) for expressions that do not evaluate to zero, or 1 (false) if they do.

						$ X=0
						$ ((X=!X)); print "$X"
						1
						$ ((X=!X)); print "$X"
						0
					

∼expression (Bitwise Negation)

Evaluates to the bitwise negated value (one's complement) of expression. It returns a ...