[PATCH] getopt.c: use integer-only function fiprintf() to save code space

[Freddie Chopin <freddie_chopin at op dot pl>]

Hello!

If you use getopt() (or any variant of this functionality) it pulls in 
fprintf() to do output to stderr in case of error. As getopt() does not 
deal with anything but strings or characters, it's much better to use 
fiprintf(), which is MUCH smaller than fprintf() - about 2.8kB for 
_vfiprintf_r() vs. 6.5kB for _vfiprintf_r(), not counting any support 
data/functions (like 4.5kB _dtoa_r()), ARMv7-M. If your program does not 
use fprintf() just using getopt increases the size of the executable by 
20kB (size of getopt() alone is ~2kB). Let's not forget RAM use, which 
is smaller in fiprintf().

Actually I think that the output could be done with fputs() and fputc() 
only, but to do that I'd first like your opinion - there's no actual 
formatting (like changing the width or whatever), just displaying. This 
would be a bit clumsy (2-7 calls to fputs()/fputc() in place of single 
f[i]printf()), but still much MUCH smaller.

Regards,
FCh

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