Uninitialized char

Question

I'm reading over a C++ class for parsing CSV files in one of my programming books for class. I primarily write in C# for work and don't interact with C++ code very often. One of the functions, getline, uses an uninitialized char variable and I'm confused as to whether it's a typo or not.

// getline: get one line, grow as needed
int Csv::getline(string& str)
{
    char c;

    for (line = ""; fin.get(c) && !endofline(c); )
        line += c;
    split();
    str = line;
    return !fin.eof();
}

fin is an istream. The documentation I'm reading shows the get (char& c); function being passed a reference, but which char in the stream is returned? What's the initial value of c?

the initial value of local variable is not defined,it could be anything — camino, Mar 10 '13 at 03:18

score 1 · Accepted Answer · edited May 23 '17 at 12:11

1

The initial value of c is undefined but it does not matter what the initial value of c is since the call to get will set the value. Since there is a sequence point after the left hand side of the || and && operators we know that all the side effects of get will have been effected and endofline will see the modified value of c.

edited May 23 '17 at 12:11

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answered Mar 10 '13 at 03:19

Shafik Yaghmour

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So `c` is set to the first character in the stream. Thanks. – Brian Mar 10 '13 at 04:18

Uninitialized char

1 Answers1