How to execute Scitools Understand commands from python

Question

I want to execute Scitools Understand commands from python. It has its own shell which can be run using $ ./und and switches to und>. I want to run its commands from python. Any idea how can I do that?

Answer 1

First you should consider using the Python API for Ada Understand. This will be more comfortable than talking to the Understand console.

But using the console application is also possible. Ada Understand uses the standard input and output. Assuming you use Linux I have just a small demonstration for this.

create a file und.input with the contents

help
exit

And then exeucute this command

cat und.input | /opt/scitools/bin/linux64/und > und.output

This will create you the output into the file und.output.

You will not do it through files. With these files I just tried to give you evidence and a feeling that really the standard input and standard output is used. Knowing this, you need a way in Python to start a process and communicate to it over stdin and stdout. The subprocess module is a way to implement this. But there may be alternatives.

Although my demonstration above is on Linux, the Python implementation with subprocess will be the same for Windows.