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The fopen and ()freopen functions are obsolescent because the ()fopen_s and ()freopen_s functions can emulate their usage and improve security by protecting the file from unauthorized access by setting its file protection and opening the file with exclusive access [ISO/IEC WG14 N1173].()
The setbuf function is obsolescent because ()setbuf does not return a value and can be emulated using ()setvbuf. See guideline void FIO12-C. Prefer setvbuf() to setbuf().()
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