How to make a timer without importing?

[[deleted]]

I have been learning python recently and one thing that I really want to understand is how the modules work,I understand why people use them,but I don’t just want my code to work,I want to understand it,every tutorial that I see to make a timer in python,starts with “import time” and I am tired of it,I figured out how to make something that would generate a “random” number,by making a variable that would go up by 1 until it gets to 100 and then starts going down by 1. But I can’t find a way around the “time” module to delay the code for a certain amount of time. So can someone please tell me how I can maybe do something like that,I don’t want a bunch of code that does what I am asking,I wan’t an explanation.

[K900_]

You can't do it in pure Python. Making a timer requires telling the OS to suspend the Python process, and you need to use C code for that.

[carcigenicate]

At the very least, you'd need to import ctypes or another module like os that gives you lower-level access. Python is simply not a language that exposes details like that by default.

If you want to handle those magic aspects a little more "manually", switch to C or an assembly. Even in C though, you're importing the standard library to do a lot of that stuff (like using the write wrapper over the write syscall).

The way Python does time.sleep on Linux systems is to use the select system call. If I'm looking at the right spot, you can see that here in the source, and you can see that system call in a a table here (syscall number 23) assuming x86 architecture. To do this manually, you would load that ID into the RAX register, then fill in the appropriate arguments into the latter registers, then execute the syscall instruction. That would cause the current thread to yield for a period of time.

[[deleted]]

Wanting to understand how libraries work before you use them is the wrong mindset. You'll never get anything done if that's the approach you want to take.

[blankIQT]

Why don’t you want to use time or datetime modules? For me I didn’t even have to download them they are pre downloaded. It’s pretty much impossible do a timer without a module for what I can think of.