It's frustrating when a library function does a worse job than 15 lines of code you wrote yourself. It's doubly frustrating when a library function is obsolete

It's frustrating when a library function does a worse job than 15 lines of code you wrote yourself. It's doubly frustrating when a library function is obsoleted and replaced wholesale rather than fixed of whatever defects it has. And file I/O is triply frustrating because there are all sorts of corner cases, plus leaked abstractions from the file system and hardware. The moral of the story is that you should never use libraries, and never do any reading or writing of files. Wait, what?