running external program in directory different from working dir

[nickvandewiele]

Hi,

My java code calls an external program. This program produces a file that is created in the working directory where my java code was called from.
I call the external program like this:

Runtime r = Runtime.getRuntime();
Process p = r.exec("C:/my_program.exe");
p.destroy();

This is what I want: my external program needs to be executed in a subdirectory of my current working directory.

Apparently, if I add the following before I call the external program

System.setProperty(user.dir,"C:/subdir/);

it has no effect on the location of the file created by the external program.

Any suggestions, ideas?

thanks in advance,

Nick

[Tolls]

Use java to move the file once it's been created?

[nickvandewiele]

That's not an option I think. Here is why:

I am using multi-threading to start multiple external programs at once. Since they all produce files with the same filename, they need to be executed in different directories. otherwise I would have files with equal filenames.

Note that I have no possibility to set the filename as an argument of the external program.

[Tolls]

Ah, OK.
A quick peek at the API and I see that exec() has a version that'll take a working directory.

[nickvandewiele]

Tolls,

your idea solved my problem. Specifying the working directory inside the runtime.exec() method was indeed the thing to do. It 's a shame i didn't notice this in the API before.

Thanks for the suggestion!

nick