Determines whether a character is a control character.
Unlike the standard C library iscntrl() function, this only
recognizes standard ASCII control characters and ignores the locale,
returning FALSE for all non-ASCII characters. Also unlike the standard
library function, this takes a char, not an int,
so don't call it on EOF but no need to cast to guchar before passing a
possibly non-ASCII character in.
Determines whether a character is a control character. Unlike the standard C library iscntrl() function, this only recognizes standard ASCII control characters and ignores the locale, returning FALSE for all non-ASCII characters. Also unlike the standard library function, this takes a char, not an int, so don't call it on EOF but no need to cast to guchar before passing a possibly non-ASCII character in.