Other types give an error. Note that I<mod> really is an infix
operator.
+=item B<len> I<expr>
+
+If I<expr> is a string, this returns the length of the string.
+
=item I<variable>
The value of the named variable.
The shell script runs as the ordinary user. It has no special
privileges.
+=head2 JOB NAMES
+
+Jobs are given implicit names (C<job$1>, C<job$2> etc.). You can also
+name jobs explicitly by preceeding the "every" or "when" statement
+with C<job "name">:
+
+ job "poll source"
+ every 10 seconds :
+ <<
+ # ...
+ >>
+
+The job name is passed to the shell script in the C<$JOBNAME>
+environment variable.
+