Variable naming conventions in documentation

[James Robb]

Hello,

Currently I am looking at the GMP library's documentation, and I am
having some difficulty understanding the naming conventions of the
variables listed in the function specifications.

Particularly the use of rop and op confuses me.

Here is the page that lists import and export functions, and due to my
confusion with the naming conventions, I am having a lot of trouble
understanding exactly what they are to do.

https://gmplib.org/manual/Integer-Import-and-Export.html

Would it be possible to get an explanation on the naming conventions of
the variables, and an explanation of what the functions do (in hopes
that I can get an even better understanding that just knowing the naming
conventions could provide)?

-- 
//-- James Robb
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