Borland C++ reference
Borland C++ 3.1 › <ctype.h>

iscntrl

raw OCR

Character classification macro.

Defined in header <ctype.h>

Syntax

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

Portability

DOSUNIXWindowsANSI CC++ only
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Remarks

iscntrl is a macro that classifies ASCII-coded integer values by table lookup. It is a predicate returning nonzero for true and 0 for false. It is defined only when isascii(c) is true or c is EOF.

You can make this macro available as a function by undefining (#undef) it.

Return value

iscntrl returns nonzero if c is a delete character or ordinary control character (0x7F or 0x00 to 0x1 F).

Example

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

int main(void)
{
   char c = 'C ;
   if (iscntrl(c))
      printf("%c is a control character\n",c) ;
   else
      printf("%c isn't a control character\n",c) ;
   return 0;
}

Differences from modern implementations

Nothing recorded yet.

Modern references

These are search links, not yet checked by hand.

Stable link: /3.1/ctype.h/iscntrl/ · short form /3.1/iscntrl/