getline function to read 1 line from a text file

This is a discussion on getline function to read 1 line from a text file within the C++ Programming forums, part of the General Programming Boards category; I've search the other threads and although I couldn't find or haven't yet found the specific answer it appears that ...

  1. #1
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    getline function to read 1 line from a text file

    I've search the other threads and although I couldn't find or haven't yet found the specific answer it appears that the getline function could be used to read one whole line of a text file.
    Could/would someone please explain how to use getline (instead of scanf because it stops at the first white space when using "%s" format specifier) to read in one line of string text from a text file.

    thanks in advance

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    Thank you code plug, but I was looking for some specific information on how to read a whole line from a text file.
    The FAQ reference doesn't even have the word file in it.

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    anything you can do with cin you can do with a stream to read files---ifstream or fstream in ios::in mode.

    //Version 1
    ifstream fin("myfile.txt");
    std::string myString;
    getline(fin, myString);
    //
    version 2
    fstream fin("myfile.txt", ios::in);
    char myString[256];
    fin.getline(myString, 255);

    in both versions the third parameter of getline defaults to the new line char such that everything up to the first newline char in Version 1 (at least til you run out of memory) and everything up to the first newline char or until 255 char have been read in in Version 2. This assumes you define a line as ending with a newline char. My syntax for fstreams may be off a bit as I hardly ever use that syntax.

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