Borland c++ compile problems

Hallo

Hello with translate the source files postgresql-8.0.0beta4 (libpg) get I
the following errors:
---
Borland C++ 5.6 for Win32 copyright (C) 1993, 2002 Borland\fe connect.c:
Warning W8017..\..\include\port/win32.h 37:  Redefinition of ' DLL IMPORT '
is not identically
Error E2209 \fe connect.c 23:  Include file ' unistd.h ' cannot be opened
Error E2209 \fe connect.c for 32:  Include file ' pg_config_paths.h ' cannot
be opened
Error E2451 \fe connect.c for 2399:  Undefined symbol ' SYSCONFDIR ' in
function parseServiceInfo
---
Where can I get the missing file?

Thanks,
Röwekamp