Hello Dave,
 > this 'fork()'
 > works? Then I could write my own version.

    Others have done that. However, in the particular code fragment, all
that fork() does is to call another process to perform parallel processing
of the index files. This can be simulated or emulated even in MS-Dos by one
of the spawn() siblings so that the calling program is suspended until
spawn() returns a result. Not quite as elegant as the fork(), but neither
is single threading. :-)

    I hope this helps.

Best wishes,
Bill.

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