Chapter 12: Problem 56

T F A file stream object’s fail member function may be used to determine if the file was successfully opened.

Short Answer

Expert verified

The fail() member function of a file stream object in C++ can indeed be used to determine if a file was successfully opened. It does this by returning a boolean value that indicates if the internal state of the stream has a failure flag set. When opening a file, if fail() returns true, then the file was not opened successfully, whereas a false value indicates a successful opening.

Step by step solution

File Stream Objects

A file stream object is an instance of the fstream, ifstream, or ofstream class, which are defined in the header file in C++. These objects are used to work with files, allowing reading, writing, and manipulation operations.

Opening a File

To open a file using a file stream object, you need to call the "open" member function providing the filename and the operation mode (read, write, etc.) as arguments. Here's a simple example: ```cpp #include #include using namespace std; int main() { ifstream inFile; inFile.open("example.txt"); // Perform operations with the file inFile.close(); return 0; } ```

fail() Member Function

The fail() member function is a part of the iostream class (base class for file stream classes) and returns a boolean value. This function checks if the internal state of the stream has a failure flag set. The internal state can be altered when some error occurs during input/output operations or when calling a member function like open().

Using fail() to Check if a File Was Successfully Opened

You can use the fail() member function of the file stream object to check if the file has been opened successfully. Here's a modified version of the previous example, now with the fail() member function to check for file opening: ```cpp #include #include using namespace std; int main() { ifstream inFile; inFile.open("example.txt"); if (inFile.fail()) { cout << "Failed to open the file."; return 1; // Exit the program with an error code } else { cout << "File opened successfully."; // Perform operations with the file inFile.close(); } return 0; } ``` In this example, we check if the fail() member function returns true, indicating a failure (file not opened successfully). Otherwise, the file was opened successfully.

Unlock Step-by-Step Solutions & Ace Your Exams!

Full Textbook Solutions
Get detailed explanations and key concepts
Unlimited Al creation
Al flashcards, explanations, exams and more...
Ads-free access
To over 500 millions flashcards
Money-back guarantee
We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

Recommended explanations on Computer Science Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

T F A file stream object’s fail member function may be used to determine if the file was successfully opened.

Short Answer

Step by step solution

File Stream Objects

Opening a File

fail() Member Function

Using fail() to Check if a File Was Successfully Opened

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Problem Solving Techniques

Data Representation in Computer Science

Databases

Computer Network

Issues in Computer Science

Functional Programming

Study anywhere. Anytime. Across all devices.