expr -- Compute a command-line expression

expr argument ...

Options:
     n         Any integer with optional sign
     string    Used with comparisons and len operator
     +         Arithmetic operators (one of `+', `-', `*', `/', `%')
     !         Unary not
     -         Unary minus
     ==        Relational operators (one of `>', `<', `>=', `<=', `==', `!=')
     &         Logical AND of previous and next expression
     |         Logical OR of previous and next expression
     len       Length of string given by next argument
     e1:e2     Set to number of characters matching regular expression e2 in
               string e1; if e2 contains any `\(...\)' sequences, result is
               concatenation of matched parts
     ( e )     Parentheses for grouping
     {
               Evaluate e2 if e1 is true, e3 otherwise; e3 defaults to 0 if
               missing
					

© 2012 by Stephen A. Ness