scanf(3) patch for C99-conformant FP parsing

Garance A Drosihn drosih at
Tue Jun 24 12:27:33 PDT 2003

At 10:57 PM +0400 6/24/03, Andrey Chernov wrote:
>On Tue, Jun 24, 2003, Garance A Drosihn wrote:
>>  #define isdigitch(Anychar)    isdigit(((int) Anychar) & 255)
>>  #define isupperch(Anychar)    isupper(((int) Anychar) & 255)
>>  #define isxdigitch(Anychar)   isdigit(((int) Anychar) & 255)
>>  #define tolowerch(Anychar)    tolower(((int) Anychar) & 255)
>Just (unsigned char) cast produce better code and more readable.
>In any case & 255 alone will be enough without needs to convert
>to (int)  first.

Yeah, I actually have two or three different versions of the
macros, depending on what I was thinking at the time. The above
lines are from a file I just happened to have open while reading
today's email.  It wouldn't surprise me too much if they include
a bit of overkill.

In any case, my main suggestion is having is*ch() macros, and
using them whenever dealing with byte-values.  I often see
code that uses one of the is*() routines with a parameter that
is 'char *'.  It's an easy mistake to make, and it can introduce
subtle bugs when porting code.

Garance Alistair Drosehn            =   gad at
Senior Systems Programmer           or  gad at
Rensselaer Polytechnic Institute    or  drosih at

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