[fpc-pascal] Porting code from Windows D2007, missing Windows functions

[Bo Berglund]

I am porting a Delphi2007 utility from Windows to Linux (Raspbian
Jessie). It uses a unit I have downloaded from the web, which was said
to support FreePascal too.

But now I am getting a number of missing identifier errors as follows
Function calls:
- SetFilePointer
- GetFileTime
- FileTimeToLocalFileTime
- FileTimeToDosDateTime
- SetEndOfFile

Constants:
- FILE_CURRENT
- INVALID_HANDLE_VALUE

It seems like these are defined in Windows and now in FPC they are
elsewhere.

The uses clause of the unit has the following content:

uses
{$ifdef MSWINDOWS}
  Windows,
{$else}
  LibC, <== Error here, not found
  Types,
{$endif}
  SysUtils;

It could not find LibC and when I asked on the Lazarus list I got a
reply to try Unix and/or BaseUnix instead. But this does not work so I
guess these functions are in another FPC unit somewhere.

What should I add to the uses clause in place of LibC to get it to
compile on Linux?

I am using FPC 3.0 and Lazarus 1.6 on a Raspberry Pi3 with Raspbian
Jessie.

-- 
Bo Berglund
Developer in Sweden