<para>The string returned by the external program requested with PROGRAM.
A single part of the string, separated by a space character, may be selected
by specifying the part number as an attribute: <option>%c{N}</option>.
- If the number is followed by the '+' char, this part plus all remaining parts
+ If the number is followed by the '+' character, this part plus all remaining parts
of the result string are substituted: <option>%c{N+}</option></para>
</listitem>
</varlistentry>