
let
Perform arithmetic on shell variables.
SYNTAX let expression [expression]
If the last expression evaluates to 0, let
returns 1; otherwise 0 is returned.
`let' is a BASH builtin command.
"Arithmetic is being able to count up to twenty without
taking off your shoes."  Mickey
Mouse
Related commands:
expr  Evaluate expressions
eval  Evaluate several commands/arguments
test  Evaluate a conditional expression