function template
<locale>

std::iscntrl

template <class charT>
  bool iscntrl (charT c, const locale& loc);
Check if character is a control character using locale
Checks whether c is a control character using the ctype facet of locale loc, returning the same as if ctype::is is called as:

 
use_facet < ctype<charT> > (loc).is (ctype_base::cntrl, c)


This function template overloads the C function iscntrl (defined in <cctype>).

Parameters

c
Character to be checked.
loc
Locale to be used. It shall have a ctype facet.

The template argument charT is the character type.

Return Value

true if indeed c is a control character.
false otherwise.

Example

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// iscntrl example (C++)
#include <iostream>       // std::cout
#include <string>         // std::string
#include <locale>         // std::locale, std::iscntrl

int main ()
{
  std::locale loc;
  std::string str="first line \n second line \n";
  for (std::string::size_type i=0; i<str.length(); ++i)
  {
    if (std::iscntrl(str[i])) break;
    std::cout << str[i];
  }
  return 0;
}


Output:

First line 

Data races

Both loc and its ctype facet are accessed.

Exception safety

Strong guarantee: if an exception is thrown, there are no effects.

See also