As Joerg Wunsch wrote: > > But I get the following compiler error: > > error: format '%S' expects argument of type 'wchar_t*', but argument 2 > > has type 'const char*' [-Werror=format=] > > printf("%S:%u\n", name, i); > > Then do as suggested, and turn off compiler warnings (and -Werror) for > this.
Sorry, I've been sick at the weekend, so my previous reply was a little terse. In general, the C standard reserves lowercase formatting letters for future standardized conversions, but leaves other characters (so namely uppercase letters) for "extensions". Thus, avr-libc's use of %S for progmem strings is fully standards compliant. It's GCC here that applies wrong assumptions. It would be cool if we could somehow "tune" that in the avr-libc printf() prototype (to avoid the pointless warning), but I'm not enough of a GCC expert on that. > > And "just for fun" I would like to know how to print wide characters > > You can't. avr-libc doesn't implement wide chars in any way. The standard's format specifier for a wide character string is "%ls". That's why GCC's notion of %S is just another kind of an extension to the standard only. We've picked %S for progmem strings, since we don't support wide characters anyway, and it seemed to be the most logical extension. -- cheers, Joerg .-.-. --... ...-- -.. . DL8DTL http://www.sax.de/~joerg/ Never trust an operating system you don't have sources for. ;-) _______________________________________________ AVR-libc-dev mailing list AVRfirstname.lastname@example.org https://lists.nongnu.org/mailman/listinfo/avr-libc-dev