How do I rewrite a line of text in a console project? c++

Question

I'm working on a c++ console project and i would like to show a percentage without making a new line each time (so that the window doesn't get clogged with thousands of lines).

Is there a way of removing the last line that was printed or something to say that the next time that i output a line it should replace the current line?

There's many ways of doing this, but most of them are dependent on your host environment (i.e. operating system). What OS are you targeting? — Cameron, Feb 05 '15 at 17:27
possible duplicate of [How can I erase the current line printed on console in C ? I am working on a linux system](http://stackoverflow.com/questions/1508490/how-can-i-erase-the-current-line-printed-on-console-in-c-i-am-working-on-a-lin) — inetknght, Feb 05 '15 at 17:27
Even though that has the same answer in it, that is based around C whereas i was asking about C++. someone looking for a solution to this in C++ would't necessarily look at C based answers. — user3797758, Feb 05 '15 at 18:03

score 17 · Accepted Answer · edited May 23 '17 at 11:54

17

You can use a \r (carriage return) to return the cursor to the beginning of the line:

This works on windows and Linux.

From: Erase the current printed console line

You could alternatively use a series of backspaces.

string str="Hello!";
cout << str;
cout << string(str.length(),'\b');
cout << "Hello again!";

From: http://www.cplusplus.com/forum/unices/25744/

Maybe mark as duplicate? I am really not sure how.

edited May 23 '17 at 11:54

Community

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answered Feb 05 '15 at 17:25

marsh

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The little "flag" link under the tags allows you to flag the question for various reasons, including potentially being a duplicate – inetknght Feb 05 '15 at 17:28
Actually, duplicate is a reason for closing, not flagging. – Steve Fallows Feb 05 '15 at 17:34

score 6 · Answer 2 · answered Sep 22 '19 at 09:12

A simple example that I tested on Linux would be:

std::cout << "Some text to display..." << "\t\r" << std::flush;

Here the \t adds a tabulation to handle slightly varying string lengths and \r sends the cursor back at the start of the line (as mentioned in other answers). std::flush is required to guarantee that the line is displayed without jumping to the next line.

score 2 · Answer 3 · edited May 23 '17 at 12:25

This is very platform-dependent and terminal-dependent. But, you may want to look at ncurses for a start: http://linux.die.net/man/3/ncurses

For Windows: How can I overwrite the same portion of the console in a Windows native C++ console app, without using a 3rd Party library?

For Linux: https://unix.stackexchange.com/questions/43075/how-to-change-the-contents-of-a-line-on-the-terminal-as-opposed-to-writing-a-new

How do I rewrite a line of text in a console project? c++

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