All the is*() ctype.h functions take an int as argument, but valid values are only EOF, and the range of values of `unsigned char'.
All, but one: the XPG4 isascii(), which has no such restriction. Quoting https://pubs.opengroup.org/onlinepubs/9699919799/ : ``The isascii() function is defined on all integer values.'' Hence the following diff. Index: isascii.3 =================================================================== RCS file: /OpenBSD/src/lib/libc/gen/isascii.3,v retrieving revision 1.13 diff -u -p -r1.13 isascii.3 --- isascii.3 17 Jul 2013 05:42:11 -0000 1.13 +++ isascii.3 11 Jun 2021 09:54:13 -0000 @@ -77,11 +77,3 @@ The .Fn isascii function first appeared in .At v7 . -.Sh CAVEATS -The argument to -.Fn isascii -must be -.Dv EOF -or representable as an -.Li unsigned char ; -otherwise, the result is undefined.
