6.003 system may hang

badly formed DO program causes error message to user but system hangs and will not respond to anything else.

TB 6.003 on Win 7 x 64 Home Premium on HP plain vanilla portable ("as issued")


DO programs


There is a clear warning in the manual to test and debug DO programs before attempting to run them as DO programs.

DO NOT attempt to run the program RUNDO.TRU. This is NOT a DO program. It is a partial utility program that is used by the editor to run other DO programs. The editor inserts extra code into this program so that it can perform its proper function. It is incomplete until the extra code has been added and will hang the computer if you attempt to run it.

DO programs have the keyword EXTERNAL on the first line. DO programs consist entirely of one or more sub-routines. DO programs do not contain an END statement. All the current pre-written example DO programs all perform properly with version 6.003.

Big John

DO hangups

OK. thank you. got it


Hi Carl,

To avoid any future problems with other users attempting to run RUNDO, I will probably move the location of this program from the TBdo folder to the main parent folder in the next release.

Big John


John, I think if someone runs ANY poorly written DO program the system will hang. I only sent you the RUNDO one as an example. However, I understand the constraints on DO and I just wanted to report the behavior, not complain about it. --CS