Very interesting, that printf has that big impact on execution of standard programs. Printf is very powerful (and one of the reasons for the success of C -- for example when you compare it with the standard library existing in Modula 2 or (old) standard Pascal), but that power also comes with a cost.
It would be interesting, how the situation is in C++ with its newer stream based output, that is more based on compiler support (as much I know). Does anybody have experiences with it?
My understanding is that the main motivation behind the introduction of iostream was to make a type-safe variant of printf. So with iostreams the _type_ of the value is determined at compile-time, but the representation (e.g. should it be stringified as dec or hex? should it be left-align or right?) needs to be determined at run-time.
In other words, the design issue is only partially solved with iostreams in terms of performance.
Thanks for the answer. Yes, I was aware, that the focus of iostreams was not on performance. But at least I would have some hope, that since less runtime-parsing would be needed (at least in standard cases), a performance benefit could arise. One of the disadvantages of printf is that even in simple cases (e.g. "%s: %d") rather much parsing is needed.
1. nothing generic is as fast as making your own custom solution
2. a lot of libc is lowest common denominator / tons of bloat. printf/sprintf probably does extra locale, multibyte charset, and thread locking shit you don't want.
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[ 2.9 ms ] story [ 22.5 ms ] threadIt would be interesting, how the situation is in C++ with its newer stream based output, that is more based on compiler support (as much I know). Does anybody have experiences with it?
My understanding is that the main motivation behind the introduction of iostream was to make a type-safe variant of printf. So with iostreams the _type_ of the value is determined at compile-time, but the representation (e.g. should it be stringified as dec or hex? should it be left-align or right?) needs to be determined at run-time.
In other words, the design issue is only partially solved with iostreams in terms of performance.
2. a lot of libc is lowest common denominator / tons of bloat. printf/sprintf probably does extra locale, multibyte charset, and thread locking shit you don't want.