Anchor(faq7)

Is there a function to return the length of a string?

The fastest way, not requiring external programs (but usable only with ["BASH"] and KornShell):

${#varname}

or

expr "$varname" : '.*'

(expr prints the number of characters matching the pattern .*, which is the length of the string)

or

expr length "$varname"

(for a BSD/GNU version of expr. Do not use this, because it is not ["POSIX"]).