The VBS library has its own data types to support all kind of operating systems. Some of the basic types are not standardized in their bit size. So the VBS has its own type definition for C and C++. In addition to the basic types, the according printing format is also defined. In Table A.3 the exact definition of each type is given.
Tabelle A.3: VBS types for C/C++
Using private definitions for types was very useful during the introduction of 64bit systems, e.g., Digital UNIX. Because of the correct type usage, there were no problems arising from the incompatible size of pointers and integers (64bit vs. 32bit). The C include definition file is named ``vtype.h'', a similar file for FORTRAN is available under the the name ``vtypes.inc''. For FORTRAN only the variable and function return types are defined by using the IMPLICIT statement from FORTRAN. The definitions shown in Table A.4 are similar to the defaults with the exception of `L' for LOGICAL. The FORTRAN type definition file has to be included into every FUNCTION and SUBROUTINE because the range of the definition is for one function only.
Tabelle A.4: VBS FORTRAN types
These type definitions declared by using FORTRANs IMPLICIT statement is almost the default except the use of ``L'' for LOGICAL. No special types are necessary for PASCAL since variable types are system independent by the language definition.
Using a set of system independent data types is important for the language binding created by TAC. Using the VBS types guarantees that the types are compatible in their bit size.