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A comment on Tell HN: C Experts Panel – Ask us anything about C. Parent comment

Re:Tell HN: C Experts Panel – Ask us anything about C by emmelaich on Tuesday April 14, 2020 @07:24PM (#22872666)
I remember that the various is* man pages noted that most of them are only defined if isascii() is true. So I always used e.g. (isascii(x) && ispunct())

FWIW, just looked at the man page (macos) and iswdigit() and isnumber() are mentioned.

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Re:Tell HN: C Experts Panel – Ask us anything about C by _kst_ on Tuesday April 14, 2020 @07:38PM (#22872778)
isascii() is not defined by ISO C. (It is defined by POSIX, but POSIX says it may be removed in a future version.)

I see that POSIX explicitly says that isascii(x) is "defined on all integer values" (it should have said "all int values").

Personally I'd rather cast to unsigned char.

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