The main Future Lab Tcl definition file has the name stdhead.tcl.

This definition file contains:

• logic to detect the required TCLDIR Tcl directory tree variable as discussed here
• definition of the system-wide constants:
  • command line switch character based on platform
  • path separator (always "/")
• source statements to Future Lab Tcl library modules

Any application that uses the Future Lab library modules should have a source statement at the top of it's file to include/insert this definition file.