Re: How does printf() works


"Sanchit" <sanchitgupta.1@xxxxxxxxx> wrote in message news:cbdde0a1-0a51-46cf-a671-dd590d918bad@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I want to know how does printf (stdio library function) works? Does
this depand on complier (I am using gcc on Linix)

Does it uses some buffer in which it stores all what needed to be
printed and in end of program it prints that or something else.

Think how you'd write a cutdown sprintf(). Let it take only %d, %c and %s format specifiers.
You'd have to set up a variable argument list, then step through the format string to determine what had been passed, then call va_arg with the right type to get the argument. Then you need to convert ints to human-readable ascii characters, and pass out to the buffer.

printf() works in roughly the same way, though with lots of bells and twiddles.


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