bool is_open();
bool is_open() const;
rdbuf()->is_open()
true if a file is open and associated with this stream object.false otherwise.1
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// ofstream::is_open
#include <iostream> // std::cout
#include <fstream> // std::ofstream
int main () {
std::ofstream ofs;
ofs.open ("test.txt");
if (ofs.is_open())
{
ofs << "lorem ipsum";
std::cout << "Output operation successfully performed\n";
ofs.close();
}
else
{
std::cout << "Error opening file";
}
return 0;
}Output operation successfully performed