How to Prevent Duplicated Last Line Reads When Reaching EOF in a C File Loop?

Fix for Duplicated Last Line Reading in EOF Loop

The original issue arises when reading from a text file until the end of file (EOF) is reached. The provided C code repeatedly grabs the last line twice because of the delayed processing of the EOF indication.

To rectify this, follow the chain of events:

1. Grab the first integer, 10.
2. Move on to 20.
3. Read 30 and continue with EOF checking.
4. Since EOF has not been reached, the loop continues. The previous value, 30, is still stored in x.
5. EOF is detected, causing x to retain the value 30 and the ios::eofbit flag to be set.
6. The value of x is output as 30, matching the previous iteration.
7. The loop condition is now evaluated, and since EOF has been encountered, the loop exits.

To address this issue, the following modifications can be made to the code:

while (true) {
    int x;
    iFile >> x;
    if (iFile.eof()) break;
    cerr << x << endl;
}

In this revised code, the loop continues until the end of file is reached, ensuring that the last line is only read once. It also handles the case of an empty file gracefully.

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