in Bash/Shell ======
Quelle((http://www.softpanorama.org/Scripting/Shellorama/Reference/string_operations_in_shell.shtml))
===== Length Operator =====
... length of the string.
The simplest one is ${#varname}, which returns the length of the value of the variable as a character string. For example, if filename has the value fred.c, then ${#fil
eeds to be escaped within a [ ] construct.
See Example 27-11 for an application of this comparison op... unquoted string alone within test brackets (see Example 7-6) normally works, however, this is an unsafe practice. Always quote a tested string.
=== Example 7-5. Arithmetic and string comparisons ===
<c... "-ne" and "!=" work.
echo
exit 0</code>
=== Example 7-6. Testing whether a string is null ===
<co
