getline(cin, var) not working

[Zia Ur Rehman]

I have a long program here...

#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using namespace std;

int main(int argc, char* argv[])
{
    string filename;
    cout << "Please enter the name of the file:\t";
    getline(cin, filename);

    if(filename.find('.') == string::npos)
    {
        char option;
        string ext;
        cout << "File extension not provided. Create file with .txt extension? Y/n\t";
        option = getchar();

        switch(option)
        {
            case 'n':
            case 'N':
            cout << "Please enter extension | <Return> to dismiss:\t";
            getline(cin, ext);
            if (!ext.empty()) {filename = filename + "." + ext;}
            break;

            case 'y':
            case 'Y':
            default:
            filename = filename + ".txt";
            break;
        }
    }

    filename = "./files/" + filename;

    int pathsize = filename.size() + 1;
    char* path = new char[pathsize];

    for (int i=0; i<pathsize-1; i++)
    {
        path[i] = filename[i];
    }
    path[pathsize-1] = '\0';


    ofstream file;
    file.open(path);
    if(file.is_open())
    {
        cout << "\nFile created: " << filename << endl;
        file.close();
    }
    return 0;
}

Line 25: Doesn't work. Doesn't even wait for input, goes ahead and puts ext = " "

I think that is because there is already a <Return> in keyboard buffer (from getchar() at line 18... So, the particular getline() at line 25 takes that pending <Return> as end of input and sets ext to empty...

I can only think of one solution. 1) Using some other function instead of getchar() above... 2) Replacing getline(cin, ext) with cin >> ext...

2 is okay because I use getline simply because cin considers a white space as termination of the string. When I want sentences or strings with spaces I use getline. Since ext is supposed to be an extension, it doesn't need spaces. So I could do with cin. But there is a problem there, too. With cin, no matter how many <Return> I press, it keeps on waiting for input. Say I don't want an extension. So when the program asks for extension, I simply press <Return> to tell it "no extension" and it understands. That works with getline, but not with cin. So, cin is not a good option.

1 is IMO the best option. But I don't know which function to choose. I want a function such that I only have to press 'y' or 'n' and it takes the input (without having to press <Return>)... No <Return> pressed, no <Return> pending... That could be done by using getch() or getche() both of which are in conio.h... And I know for a fact that neither conio.h nor any of the mentioned functions are any close to being standard. I want to keep it standard and simple at the same time.

I posted another thread asking for options against 1. I didn't have any problem with getline at that time, but I wanted the input without <Return> anyway. Now, finding a solution is more important since this is effecting getline() too. That thread is located here: http://www.cplusplus.com/forum/beginner/33659/

What do I do?

[Null]

Put std::cin.ignore( std::numeric_limits<std::streamsize>::max(), '\n' ); on line 19 - it will remove '\n' from the input buffer.

[Zia Ur Rehman]

Will it "remove" '\n' from the buffer or just ignore if it's there?

And what about option 2?

[Null]

Will it "remove" '\n' from the buffer or just ignore if it's there?

I'm not sure about that but the documentation^* says

Extracts characters from the input sequence and discards them.

^* http://www.cplusplus.com/reference/iostream/istream/ignore/

[Zia Ur Rehman]

Thank you very much.
And I got an answer for option 2 in my other thread: http://www.cplusplus.com/forum/beginner/33659/
That is working, too... So I can use any of them. I am using both; this one just to make sure there are no pending chars from buffers in case I call getline somewhere else.