Synopsis:
   $substr(<substring> <search string>)
   $rsubstr(<substring> <search string>)

Technical:
   These functions search for <substring> in <search string> and return the
   index to it. rsubstr is identical to substr, except it searches from
   the end to the beginning.

Practical:
   They can be used to search for specific things in output from a server,
   or as an alternative to $match(*substring* searchstring).

Returns:
   -1 if <substring> not found in <search string>
   index to <substring> in <search string> if found

See Also:
   match(6); rmatch(6)