This is an easy question, but I couldn’t find an explanation anywhere
I’m using fopen in C++, and I have the option to either use
“r+b” (Read and Write)
Or
w+b” (Read Write and Truncate)
What is the meaning of Truncate? What is the difference between “r+b” and “w+b”? I understand the mathematical meaning of truncate is removing precision after a certain number of decimal points, but I don’t understand the exact meaning in the C++ context.
Thanks,
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Answer
“truncate” means that the file will be set to size 0
on opening.
"w+b"
will give you an empty file (creating it if it didn’t exist) that you can read and write to.
"r+b"
will fail if the file does not exist; and if the file does exist then the file remains unchanged for now and you can read or write to it.