How to write a program that works on different OS? - operating-system

Question

The question I'm asking is a bit unclear, I think it's a bit hard to explain it with only one line. Here's my situation: I have a Bitbucket repertory which is cloned in both an Linux environment and Windows environment. The problem I have is:
1- I need to read and write from files and the paths to the different locations must be changed every time I commit and push. Hence, if I was working on Windows and made a push, when I go back to Linux and need to pull and change the paths I used.
2- I'm running selenium with Python. In order to make it work on my Linux serverless machine, I need to create a virtual display with pyvirtualdisplay library. Hence, some code that needs to be executed on my Linux machine must not be executed on my Windows machine.
So the problem I got is if I work on my Windows machine, I need to comment out the lines that creates the virtual display.
These two problems takes me a lot of time, because everytime I pull in a different machine, I can't directly work on the code, but have to change the code first.

Answer 1

Pretty simple. What you are looking for is to import the 'os' module.
import os
Then you can get the "name" of the current running Operating System by checking: os.name.
You can then base if or case statements, or however you want to manage your code, on what OS is reported.
To be clear, I would wrap the code I want to run only in a certain environment in an if statement that determines which OS is running and runs the appropriate code block based on the result.
if [[ os.name == "nt" ]]; then
;do Windows stuff
else
;do linux stuff
fi
Additional Note! That was psuedocode based on general Bash scripting.
This is Python psuedocode:
if os.name == "nt":
; Do Windows Stuff
else:
; Do Linux Stuff

Answer 2

Your first issue can be solved by handling the paths in a configuration file instead of hard-coding them in the program itself (and possibly using the pathlib or os.path modules for the actual path manipulations), then telling git to ignore the config file. You can then create appropriate configurations on each system, and git won't bother them at all.
Your second issue can be solved by using any of the various methods Python gives you to figure out what OS you're running on, and then using simple conditional statements to match on them. In theory, you could do the same for the paths, but it really is better in the long run to get in the habit of properly separating runtime configuration like that from program logic. Options for this include:
os.name: Contains posix, nt, or java, which identifies what type of OS you're on. java for Jython, nt for Windows,posix` for pretty much everything else. Useful when you just care about certain low-level OS semantics.
sys.platform: Contains a generic name for the underlying OS ABI. win32 for Windows, darwin for macOS, linux for Linux, and the name of the OS for other UNIX variants. This lets you check for particular underlying platforms, and is generally what you should use for conditional code that only runs on one platform. Make sure to always check this with a construct like sys.platform.startswith('X'), as some platforms and Python implementations include version info after the OS name.
platform.system(): Similar to sys.platform, except that the returned string is more user-friendly (Windows for Windows, Linux for Linux, etc), and it returns an empty string if it can't figure out what OS you're on. Useful for displaying the OS to the user, but not for doing conditionals (because it's free-form and may not always return useful information).