HOST comands in PL/SQL with DBMS_PIPE

I've heard that it is possible with DBMS_PIPE package to make PL/SQL execute OS commands (like HOST command in SQL*Plus), but I can't find how.

Have anybody made such construct ?

Jure

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 ! Jurij Modic                            Republic of Slovenia !


 !  tel: +386 61 178 55 14                Ministry of Finance  !

 !  fax: +386 61  21 45 84                Zupanciceva 3        !


 !  e-mail: jurij.modic_at_mf.sigov.mail.si  Ljubljana 1000       !


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