Chapter 12: Problem 6

Under what circumstances is a file stream object's ios: : hardfail bit set? What member function reports the state of this bit?

Short Answer

Expert verified

Answer: The 'ios::hardfail' bit is a flag in a file stream object that is set when a file stream operation results in an unrecoverable error, such as a disk-full error or an access rights violation. The member function that reports the state of the ios::hardfail bit is 'rdstate()'. It can be checked by using the bitwise AND operator with the value returned by 'rdstate()' and the 'ios::hardfail' flag.

Step by step solution

Understand file stream objects and ios::hardfail bit

File stream objects are used to handle operations on files. They can be used for input/output operations on files. A file stream object has several bit flags (like the ios::hardfail) that are used to indicate the state of the object. The ios::hardfail bit is a flag that is set when a file stream operation results in an unrecoverable error, such as a disk-full error or an access rights violation.

Identify when the ios::hardfail bit is set

The ios::hardfail bit is set under the following circumstances: 1. If an operation leads to an unrecoverable error, for example, a disk-full error. 2. When there is a violation of access rights, such as trying to open a read-only file for writing.

Determine the member function that reports the state of the ios::hardfail bit

The member function that reports the state of the ios::hardfail bit is 'rdstate()'. This function returns an integer value that represents the stream's error state flags. To check the state of the ios::hardfail bit specifically, we can use the bitwise AND operator with the value returned by 'rdstate()' and the 'ios::hardfail' flag: ```cpp #include #include int main() { std::fstream file("example.txt", std::ios::in | std::ios::out | std::ios::trunc); // Operation that could potentially set the ios::hardfail bit file << "sample text"; file.flush(); if (file.rdstate() & std::ios::hardfail) { std::cout << "ios::hardfail bit is set" << std::endl; } else { std::cout << "ios::hardfail bit is not set" << std::endl; } file.close(); return 0; } ``` In this example, if the operation of writing to the file triggers an unrecoverable error, the ios::hardfail bit will be set, and the output will be "ios::hardfail bit is set". Otherwise, the output will be "ios::hardfail bit is not set".

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.

Under what circumstances is a file stream object's ios: : hardfail bit set? What member function reports the state of this bit?

Short Answer

Step by step solution

Understand file stream objects and ios::hardfail bit

Identify when the ios::hardfail bit is set

Determine the member function that reports the state of the ios::hardfail bit

One App. One Place for Learning.

Most popular questions from this chapter

Recommended explanations on Computer Science Textbooks

Computer Network

Big Data

Data Representation in Computer Science

Functional Programming

Game Design in Computer Science

Problem Solving Techniques

Study anywhere. Anytime. Across all devices.