mflex is output if the start and current positions are the same.
</P>
<P>
Callouts numbered 255 are assumed to be automatic callouts, inserted as a
result of the <b>/C</b> pattern modifier. In this case, instead of showing the
callout number, the offset in the pattern, preceded by a plus, is output. For
example:
<pre>
    re&#62; /\d?[A-E]\*/C
  data&#62; E*
  ---&#62;E*
   +0 ^      \d?
   +3 ^      [A-E]
   +8 ^^     \*
  +10 ^ ^
   0: E*
</pre>
The callout function in <b>pcretest</b> returns zero (carry 