How may I call out function _OWERSJA form WINIP.dll where p1,p2 there are names of files (p1 - file in, p2 - file out)

p1:="OWERSJA.IN"
p2:="OWERSJA.OUT"

err:=_OWersja(p1,p2)

declare DLL_TYPE_BYTE _OWersja(DLL_TYPE_LPTSTR cFile1, DLL_TYPE_LPTSTR cFile2) in winip.dll

Try this:

DLL FUNCTION _OWERSJA( cFile1 AS LPSTR, cFile2 AS LPSTR ) AS LONG PASCAL LIB "winip.dll"

in C

unsigned char __declspec(dllimport) _cdecl _OWersja(char in, char out);

my source:

include "FiveWin.ch"

//---------------------------------------------------------------------------//

function Main()

p1:="OWERSJA.IN"
p2:="OWERSJA.OUT"
err:=_OWersja( p1, p2 )
msginfo(err)

return nil

//---------------------------------------------------------------------------//
DLL FUNCTION _OWERSJA( cFile1 AS LPSTR, cFile2 AS LPSTR ) AS BYTE PASCAL LIB "WinIP.dll"

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