isxdigit Function (Macro)

ctype.h

short isxdigit (short c);

Checks whether a character is a hex digit.

isxdigit returns nonzero if c is a hexadecimal digit ('0' to '9', 'A' to 'F' or 'a' to 'f'), otherwise it returns zero. It is an inline function which is implemented using GNU C smart macros, which expands to a medium-sized code.