/************************************************************************ * * Purpose: Program to demonstrate the following functions: * isalpha, isdigit, isspace. * The same principles apply to isalnum, iscntrl, isgraph, * islower, isprint, ispunct, isupper, isxdigit * * Author: M. J. Leslie * Date: 09-Mar-94 * ************************************************************************/ #include /* printf */ #include /* isalpha isdigit isspace etc */ #define FALSE 0 #define TRUE 1 /* function declarations */ int char_type(char); main() { char ch; /* get a character from the keyboard */ printf(" Please enter a charcater => "); ch = getc(stdin); char_type(ch); /* Figure out the character type */ } /**************************************************************** decide the character type. *****************************************************************/ int char_type(char ch) { /* returns non zero if A-Z or a-z */ if ( isalpha(ch) != FALSE) printf("%c is an Alpha character.\n",ch); /* returns non zero if 0-9 */ if ( isdigit(ch) != FALSE) printf("%c is a numeric character.\n",ch); /* returns non zero if a space, CR, Tab, NL FF */ if ( isspace(ch) != FALSE) printf("%c is white space\n", ch); }