The following works as a program, but not as a unit (used e.g. by an empty program). It gives the following runtime message (DJGPP and Linux): ?GPC runtime error: (gpc-rts) _p_initfdr() has not been called for file (#701) {$define u} {$IFDEF u} UNIT printer; INTERFACE {$ENDIF} USES System; VAR Lst:Text; {$IFDEF u} IMPLEMENTATION TO BEGIN DO {$ENDIF} BEGIN Assign(Lst,'LPR'); Rewrite(Lst); writeln(Lst,'Test'); Close(Lst) {$IFDEF u} END; {$ENDIF} END. Apropos: Did anyone write a portable printer unit yet? -- Frank Heckenbach, Erlangen, Germany heckenb@mi.uni-erlangen.de Turbo Pascal: http://www.mi.uni-erlangen.de/~heckenb/programs.htm Internet links: http://www.mi.uni-erlangen.de/~heckenb/links.htm