I have started rewriting my older software to work with the newer Haiku. At the same time I have been improving the code and it`s speed. The first package I have rewritten in my FileFilter program. The new 0.80 version works fine with Haiku-OS but three years ago I ask if it was possible to make a program work like the FORMAT command did on the Amiga. At the time I was told no! I am hoping that with all the changes to the source code that maybe it can be done now. On the Amiga if you started FORMAT from the CLI you got a CLI program, if however you double clicked the icon that pointed to the same code you got a GUI version of the program. This is the behaviour I would like to emulate. In Haiku-OS I test how many arguments are passed to the program at start-up. If the program see more than zero arguments being passed it assumes it is a CLI program and only runs in the terminal, if the program see no arguments it is assumed that the program was invoked by the GUI and run with a GUI interface. The problem if I just enter the program name with no arguments in the CLI (Terminal) the GUI version is invoked. Is there any way for a single Haiku-OS program to tell what environment invokes the program?