function
<cctype>

isspace

int isspace ( int c );
Check if character is a white-space
Checks whether c is a white-space character.

For the "C" locale, white-space characters are any of:
' '(0x20)space (SPC)
'\t'(0x09)horizontal tab (TAB)
'\n'(0x0a)newline (LF)
'\v'(0x0b)vertical tab (VT)
'\f'(0x0c)feed (FF)
'\r'(0x0d)carriage return (CR)

Other locales may consider a different selection of characters as white-spaces, but never a character that returns true for isalnum.

For a detailed chart on what the different ctype functions return for each character of the standard ASCII character set, see the reference for the <cctype> header.

In C++, a locale-specific template version of this function (isspace) exists in header <locale>.

Parameters

c
Character to be checked, casted to an int, or EOF.

Return Value

A value different from zero (i.e., true) if indeed c is a white-space character. Zero (i.e., false) otherwise.

Example

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/* isspace example */
#include <stdio.h>
#include <ctype.h>
int main ()
{
  char c;
  int i=0;
  char str[]="Example sentence to test isspace\n";
  while (str[i])
  {
    c=str[i];
    if (isspace(c)) c='\n';
    putchar (c);
    i++;
  }
  return 0;
}


This code prints out the C string character by character, replacing any white-space character by a newline character. Output:
Example
sentence
to
test
isspace

See also

isgraph
Check if character has graphical representation (function )
ispunct
Check if character is a punctuation character (function )
isalnum
Check if character is alphanumeric (function )
isspace (locale)
Check if character is a white-space using locale (function template )