Java and c++ user input on M1 MacBook Pro

Post the shortest C++ source code example you can (no Java here), and related context relevant to the input; the code, and use of Terminal.app or some other emulator, settings (Unicode, UTF-8, ASCII, etc) for the terminal, etc.

The C++ getline() call can be subtle and quick to anger, particularly around cin.

Here's a tweaked example, with a cin.ignore() added and with a header-file fix (using the C++ header and not the C header), and also showing a different means of performing the user input query. This sequence uses bash.

$
$ xcodebuild -version
Xcode 13.3.1
Build version 13E500a
$ sw_vers
ProductName:	macOS
ProductVersion:	12.3.1
BuildVersion:	21E258
$ clang++ -std=gnu++17 -o x x.cpp
$ ./x
Enter your favorite color >> 
blue
You picked blue
Enter your favorite number >> 
6  
You picked 6
$ cat x.cpp
#include <cstdio>
#include <iostream>
using namespace std;
int main(int argc, const char * argv[]) {
    string answer;
    cout << "Enter your favorite color >> " << endl;
    cin >> answer;
    cin.ignore();
    cout << "You picked " + answer << endl;
    cout << "Enter your favorite number >> " << endl;
    getline( cin, answer );
    cout << "You picked " + answer << endl;    
    return 0;
}
$ 

I'd guess the Oracle Java issue has a similar origin, but no Java is here installed, nor is Java usage here common.

PS and entirely FWIW: when posting questions and source code reproducers for problems, I'd suggest using the source code insertion button <>, and also posting the macOS and Xcode versions as those are (generally) more central to a C++ question than is the hardware, as well as posting the particular command-line clang++ command used.

LouisCyphre wrote:

Hi,

Thanks for the help but it still bahaves the same, program just doesn't wait for user's input, spits out everything at once.

I'll kepp searching, I guess.

Louis

So to confirm, you used and tested with the app source code I provided, built with the clang++ command shown, and it did not prompt for input?

Interesting.

(That is a command-line app, so it’s necessarily built as a command-line app within Xcode, and build with the clang++ command shown from the command line, and run from Terminal.app or some other emulator.)

What are your terminal settings for character encoding?

Have you tried using the Apple Terminal.app and not another emulator?

Which Xcode and which macOS?

(I’m still not entirely sure what you’re actually doing here, either. Running it in vim or emacs? That’s probably possible with some customizations or extensions, but lets get the code working at the command line first…Edit, exit, compile and link, run and test, repeat, etc.)

I do not yet understand how vim and emacs text editors are involved here, though you can and do reference those repeatedly.

With a default install on macOS, AFAIK the text editors are not involved in C++ processing cin for input, or getline().

Because unless you're using those editors as an IDE and are trying to build and run (and the results failing to prompt, as you keep repeating) within the context of those text editors—with an add-on plug-in or other such customization or makeprg or such—those editors are not involved here.

And if the add-on plug-in or customization you are using here is not working, well, at the risk of demonstrating my hammerlock grasp of the obvious, stop using it and build using the classic command-line pattern, and contact the folks maintaining the vim or emacs plug-in for assistance.

Here's an example of what I'd expect to happen:

https://stackoverflow.com/questions/21474662/compiling-and-running-a-c-program-with-vim#21477312

If you're doing something different than this, please be more specific.

I use vim a whole lot, quite possibly with some old-fashioned habits, and this isn't a sequence or situation I've encountered. But as an IDE, Xcode... Which runs circles around older methods.

Using the exact code and compilation that MrHoffman provided, and with either vim 8.2.3455 from the command line, or MacVim 8.2.3455 on macOS Monterey 12.3.1, I can enter !x or !~/Code/CXX/x and have interactive prompts and inputs just as if I ran the same code from the command line outside of vim. I don't touch emacs with a stick.

Did you omit the cin.ignore() line which would flush the remnant newline from the buffer?

Greetings, LouisCyphre.

It sounds like you'll want to reach out to Apple's Developer Support.

Support - Apple Developer

Best wishes. 

Good you’ve sorted it. Next time, post a reproducer.