14 The HLAPARSE Command Line
The HLAPARSE program was written with the expectation that it would always be invoked by some other program (e..g, HLA/HLA.EXE). If you really know what you are doing, you can invoke HLAPARSE from the command line manually. However, other than testing or debugging the HLA system, there really is no need to manually invoke HLAPARSE. All the functionality available from the HLAPARSE command line is also available from the HLA command line. Further, HLA does sanity checks on the command line parameters, fills in optional values, fetches environment variables, and so on. HLAPARSE expects a program like HLA to provide a correct set of command-line parameters; it does not do all the checks on the parameters and if they are incorrect, it may silently fail. As such, it's not intended to be used by end-uses as a matter of course.
There is one case where you might be interested in invoking HLAPARSE via some other means than via the HLA program - when writing a replacement for HLA. A good example of this is the HIDE (HLA Integrated Development Environment) system. If you're interested in writing a program that invokes HLAPARSE directly, then you'll want to learn about the HLAPARSE command-line parameter set. However, this manual is not the place to discuss such things, as they are considered internal to the HLA system. You can view the possible command-line parameters by typing "HLAPARSE -?" at the command line. However, to truly understand their semantics, you'll want to open up the hlaparse.bsn source file and study the code at the very end of the file (warning, it's about 100,000 lines long, so you'll need a good editor to open and look at this code). I (Randy Hyde) will be more than happy to answer any questions via email or via some forum concerning these parameters; they are not, however, something I want to document and give people the impression that they are available for everyday use.