I am reading financial data from my broker in real time through a websocket API. The client is written in Python. I have another C++ program that reads that data, but the way I am communicating with the python script is through a physical text file.
My questions are...
1) Does constantly rewriting the textfile, opening, reading and closing it everytime affects performance? If so, what's a better way to do it? Performance on my application is crucial.
2) Would using named pipes be a better option? Or is that pretty much the same as writing and reading to a text file?
Modern OS support many different IPC. Pipes, named pipes, sockets, memory mapped files, ... The choice of one solution or the other is very dependent of your application. But broadly speaking, all of them should be "better" than using a plain-old-file.
As IPC are objects managed by the OS, they are not dependent of the language used to write the various process. Some IPC have a file semantic (pipes, named pipes). Other require the use of some dedicated system primitive (mmap). But C++ and Python (and many other language) will support the required system call. In fact, IPC are great to help software written in different languages to speak together.