basic_filebuf::is_open
Indicates whether a file is open.
bool is_open( ) const;
Return Value
true if the file pointer is not a null pointer.
Example
// basic_filebuf_is_open.cpp
// compile with: /EHsc
#include <fstream>
#include <iostream>
int main( )
{
using namespace std;
ifstream file;
cout << boolalpha << file.rdbuf( )->is_open( ) << endl;
file.open( "basic_filebuf_is_open.cpp" );
cout << file.rdbuf( )->is_open( ) << endl;
}
false true
Requirements
Header: <fstream>
Namespace: std