isxdigit, isxdigit_l—hexadecimal digit predicateSynopsis
#include <ctype.h> int isxdigit(int c); #include <ctype.h> int isxdigit_l(int c, locale_t locale);
Description
isxdigit is a macro which classifies singlebyte charset values by table
lookup. It is a predicate returning non-zero for hexadecimal digits,
and 0 for other characters. It is defined only if c is
representable as an unsigned char or if c is EOF.
isxdigit_l is like isxdigit but performs the check based on the
locale specified by the locale object locale. If locale is
LC_GLOBAL_LOCALE or not a valid locale object, the behaviour is undefined.
You can use a compiled subroutine instead of the macro definition by
undefining the macro using ‘#undef isxdigit’ or ‘#undef isxdigit_l’.
Returns
isxdigit, isxdigit_l return non-zero if c is a hexadecimal digit
(0–9, a–f, or A–F).
Portability
isxdigit is ANSI C.
isxdigit_l is POSIX-1.2008.
No supporting OS subroutines are required.