Re: ICU4C proposal: Formalizing the ustdio format specifiers

General comments:

It is a great pain for portable code that C does not specify the widths of its built-in types. ICU4C 
uses int32_t, uint16_t etc. for good reasons. There is no way we will design any API for 
unknown-width types.

I understand how C got this way. Sometime in the last 15 years they should have defined C types more 
strictly though.

It has always worried me that there was no sure way to format an int32_t with printf(). Do I use %d 
or %ld? (On Win16 I would need the latter.)

Similarly, %ls and %S and such are as useless (or even more so) for portable code using standard 
printf() as wchar_t itself.

George's proposal simply contains format specifiers for what makes sense for APIs with defined-width 
types.

The one place where I am not sure myself is %ld vs. %lld (and cousins %lu, %llx etc.). It would be 
nice and consistent to have each width specifier (h, <no width>, l) stand for a unique width (16, 
32, 64 bits respectively); however, I know that some code is using %ld for 32-bit types (see above), 
and so porting might be a bit safer if both <no width> and (ell) were 32 bits wide and then (ell 
ell) be used for 64 bits. I don't care enough myself so far about this point to make a strong stand 
one way or another.

markus

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