Why fstream prints out last record of a file

Question

why is it that the last record of a binary file is being printed out twice?

while( (inFile)
{
    inFile.read(reinterpret_cast <char*> (&acc), sizeof(acc));  
    display(acc);
}

For similar reasons, as outlined in [Why is iostream::eof inside a loop condition considered wrong?](https://stackoverflow.com/questions/5605125/why-is-iostreameof-inside-a-loop-condition-considered-wrong). — Algirdas Preidžius, Mar 25 '19 at 12:08
You are displaying the result, disregarding the success of the reading. — Jean-Baptiste Yunès, Mar 25 '19 at 12:20

score 2 · Answer 1 · answered Mar 25 '19 at 12:12

Because your code should read

while (inFile.read(reinterpret_cast<char*>(&acc), sizeof(acc))
{
    display(acc);
}

Your version only tests for failure after you've printed the failed read. Or to put it another way while (infile) is not a test that the next read will succeed, it's a test that the last read succeeded.

Why fstream prints out last record of a file

1 Answers1