{{keywords>wiki library source code example reference}}
===== iscntrl =====
<code c>
    int iscntrl(int chr);
</code>
Tests if a character a control character

===== C Sourcecode Example =====
<code c>
#include <stdio.h> /* including standard library */
//#include <windows.h> /* uncomment this for Windows */

#include <ctype.h>

int main ( void )
{
  int i;
  char string[11]="Test\n-!&%1";
  for (i=0; i <= 11;i++)
    {
     if ( iscntrl(string[i]) != 0 )
      {
       printf("Character %i is a control char\n",i);
      }
    }
  return 0;
}
</code>
==== output ====
    user@host:~$ ./iscntrl 
    Character 4 is a control char
    Character 10 is a control char
    Character 11 is a control char