#include <ctype.h> int isupper(int c);
isupper
tests an integer value c
to determine whether it is an
uppercase alphabetic character.
isupper
returns 0 if the character is not an uppercase alphabetic
character, or a nonzero value if it is. If the argument is EOF
, 0
is returned.
isupper
on a noncharacter argument other than EOF
is undefined. The definition of an uppercase character is
locale dependent. Do not assume that isupper
returns either 0 or 1.
#include <ctype.h> #include <stdio.h> #define MAXLEN 40 main() { char id[MAXLEN +1]; char *text; char input[MAXLEN +1]; int i; printf("Enter a string (maximum of %d characters):n", MAXLEN); text = gets(input); /* Copy uppercase "identifier" from text to id. */ for (i = 0; i < 40 && isupper(text[i]); ++i) id[i] = text[i]; id[i] = '0'; /* Only initial uppercase characters get copied. */ printf("%sn", id); }
isalpha
, islower
, tolower
, toupper
Copyright (c) 1998 SAS Institute Inc. Cary, NC, USA. All rights reserved.