iscntrl()

test a character to see if it's a control character

Synopsis:

#include <ctype.h>
int iscntrl( int c );

Description:

The iscntrl() function tests for any control character. A control character is any character whose value is from 0 through 31.

Returns:

A nonzero value when the argument is a control character, otherwise zero.

Examples:

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

char chars[] = {'A', 0x09, 'Z'};

#define SIZE sizeof( chars ) / sizeof( char )

void main()
  {
    int   i;

    for( i = 0; i < SIZE; i++ ) {
      printf( "Char %c is %sa Control character\n",
        chars[i],
        ( iscntrl( chars[i] ) ) ? "" : "not " );
    }
  }

produces the output

Char A is not a Control character
Char     is a Control character
Char Z is not a Control character

Classification:

ANSI

See also:

isalnum(), isalpha(), isdigit(), isgraph(), islower(), isprint(), ispunct(), isspace(), isupper(), isxdigit()