Name
let
Synopsis
letexpressions
((expressions
))
Perform arithmetic as specified by one or more
expressions. expressions
consist of numbers, operators, and shell variables (which don't need
a preceding $
). Expressions must
be quoted if they contain spaces or other special characters. The
(( ))
form does the quoting for
you. For more information and examples, see the section Arithmetic Expressions, earlier in this reference. See
also expr(1).
Examples
Each of these examples adds 1 to variable i
:
i=`expr $i + 1` All Bourne shells let i=i+1 Bash let "i = i + 1" (( i = i + 1 )) (( i += 1 )) (( i++ ))
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