isspace

isspace

White Space Test

Portability: ISO/ANSI C conforming, UNIX compatible

SYNOPSIS
DESCRIPTION
RETURN VALUE
CAUTION
EXAMPLE
RELATED FUNCTIONS
SEE ALSO

SYNOPSIS

#include <ctype.h>

int isspace(int c);

DESCRIPTION

isspace tests an integer value c to determine whether it is white space; that is, a blank, tab, new line, carriage return, form feed, or vertical tab character. In the 5370 and POSIX locales, isspace returns true only for standard white-space characters.

RETURN VALUE

isspace returns 0 if the character is not white space, or a nonzero value if it is. If the argument is EOF , 0 is returned.

CAUTION

The effect of isspace on a noncharacter argument other than EOF is undefined. Do not assume that isspace returns either 0 or 1.

EXAMPLE

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>

main()
{

   int c, n;
   puts("Enter a character when prompted.. even spaces are OK.");
   for (n = 1;; n++ )  {
      puts("Enter now (q to quit):  ");
      c = getchar();
      if (c == 'q') exit(0);
      printf("The character you entered %s a space character\n",
             isspace(c) ? "is" : "is not");
      if (c != '\n')
         getchar();                      /* Read the new line. */
   }
}

RELATED FUNCTIONS

iscntrl , isgraph

SEE ALSO

Character Type Macros and Functions

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