Handling processes

[Dennis]

I am busy researching commercially available software copy protection systems to protect a system I have developed in LB.

I sent out a general requirement statement and one of the potential vendors responded to say that it would be relatively easy to use their product provided LB could do the following

1. Spawn a process from the application.

2. Write commands to the spawned process’s output stream

3. Read events from the spawned process’s input stream


I think the first is possible by using something like a RUN command but I am not too sure about the other two.

I will do some further reseaech with LB but it would be helpful if someone on the forum has definite answers and/or code for the above.

Any help/info would be greatly appreciated.

Regards
Dennis

[Walt Decker]

1. Spawn a process from the application.

2. Write commands to the spawned process’s output stream

3. Read events from the spawned process’s input stream

#1 is probably an exe.

#2 is probably a DLL that handles input to the exe and could probably be accomplished with a CALLDLL call provided you are given the DLL handle and function moniker.

#3 could be one of two things, a return value from the CALLDLL or a CALLBACK that you would have to monitor and possibly respond to as the security process progresses. These are doable depending on how intensive the CALLBACK is if it requires a CALLBACK.

[Dennis]

Hi Walt

Thanks for responding. I have now received further feed back from the potential vendor.

Point 1 appears to be something (a .EXE) which can be run via a command line so I assume a "RUN" command will suffice.

According to the vendor, points 2 and 3 can also be done through the command line. The information been read and written is text i.e. probably the license information.

Regards
Dennis

[Walt Decker]

Dennis,

LB can start the .exe with "RUN" but, from your description, I doubt that you can get any return information. Looking at the description for "RUN", it does not use SHELL and there is no provision for return parameters.

From your description of points 2 and 3, I can not see how they can be implemented through the command line unless there is no interaction between your calling app and the encryption app after it is started. In that case, all the information would have to be sent one time through the command line.

[Rod]

We can run .bat files with the run command so it might be possible to script a batch file that starts the .exe then sends it info and receives the response, piping it to a file. But the devil is in the detail.

[Dennis]

Hi Rod and Walt
I previously used the concept of writing a .bat file from within an LB program, executing it, and then use piping to get back the output for another problem which I had.
I am going to try playing with that approach again but as you say Rod, the devil is in the detail.
I hoped that thre might be a cleaner solution.
Thanks for the responses, I will keep everybody in the loop.
Regards
Dennis