(Only related to Eddie Penninkhof's XBasic version (V6.#.#)
This small file resides in the xbpath\bin\  directory along with your xbasic binaries.
EddieBasic needs to know where it can find include files and libraries so they need to be defined in environment variables.
If you don't have these set correctly you may find problems with compiling your source to an executable.
If you installed XBasic from the self-installable module that you downloaded from sourceforge, chances are that the values are set correctly (if you did not replaced or renamed directories afterwards).
If you installed XBasic from within the Zipped archive there is a big chance you need to adjust the XBVARS.BAT to make it work:

You can either call XBVARS.BAT each time you start XBasic from within a DOS session but easiest and best thing is to add the following line to your AUTOEXEC.BAT when running in Win'9X:
CALL drive:\pathtoxb\bin\XBVARS>BAT

The following values are important to be set properly in the DOS environment: PATH, LIB, INCLUDE, XBDIR. The following is an example of where an XBasic distribution can be installed:
@echo off
REM Changes the following paths into the right ones; Replace C:\XB by the
REM directory into which you installed XBasic
set PATH=E:\DevTools\XB\bin;%PATH%
set LIB=E:\DevTools\XB\lib;%LIB%
set INCLUDE=E:\DevTools\XB\include;%INCLUDE%

You can check if the procedure went well by performing the following command on a DOS-prompt:
C:\>SET [enter]

If you notice that lines are missing or you get errors that you have too less environment space then you also need to add a line in the CONFIG.SYS to extend your environment memory to be able to add the values to the variables:

/E:4096 will create a 4K buffer for your environment variables, that supposed to be enough.

If you have Win9x you can set "program properties" like AUTOEXEC.BAT values and CONFIG.SYS values in order to emulate a full DOS session containing the environment variables if you don't want to call them from the AUTOEXEC.BAT before Windows is started (Handy in cases you want to have different XBasic environments for testing).
In WinNT /2000 you can set the environment variables in the properties of the "My computer" icon under "Environment".

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