More 'standard' system("cls")?

[chrisname]

I've been using system("cls") to clear a DOS window for a while now, but I don't want to use system() commands any more. Is there a more standard way I could do this? I tried using gotoxy(int x, int y) style functions, where I would go to the first character of each line (gotoxy(i, 0), where i is the current iteration in a loop), and writing about 50 spaces but it did not work.

Is there another way?

If you didn't understand my first paragraph, this is what I meant

void gotoxy(int x, int y) {
COORD coord; // coordinates
coord.X = x; coord.Y = y; // X and Y coordinates
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), coord);
}

void clrscr() {
int i;
for (i=0; i<100; i++) {
  gotoxy(i, 0);
  cout << "                                                  "; /* Print 50 spaces */
}
gotoxy(0,0);
}

But, while it sort of worked, it takes too long to do whereas system("cls"); is virtually instantaneous.

[helios]

http://www.cplusplus.com/forum/articles/10515/

[Duthomhas]

http://www.cplusplus.com/forum/articles/10515/
:-)

[edit] arrgh.. quit stalking me! J/K XD

[z05DSL3A]

Clear the screen
http://www.cplusplus.com/forum/articles/10515/

[firedraco]

Oh, what the heck...
http://www.cplusplus.com/forum/articles/10515/

[S6k9GNh0]

http://www.cplusplus.com/forum/articles/10515/

I think I'm going to make a site dedicated to things like this...

[chrisname]

Thanks everyone. I love that you all posted the same link...

[S6k9GNh0]

In the article, there's something in there similar to what you did. It just call a line break 100 times to clear the screen but that's easily not the best way so I don't recommend it.

[Duthomhas]

BTW, I should note that in my articles, you should often take the hardest look at the "OS-specific ways" -- they are usually what you really want to do.

[jloundy]

i think printing 50 useless space is probably more problimatic than just using system("cls");
its one of those things you cant just stop using because people tell you too, just use it until it gives you issues. my 2 cents

[helios]

i think printing 50 useless space is probably more problimatic than just using system("cls");

Considering printing 50 lines will work anywhere (where the console has at most 50 lines), but system("cls"); won't, I don't think so.

[jloundy]

you got me

[S6k9GNh0]

I either due the OS based version or I use NCurses...I don't really code in command based apps unless I'm testing a theory anyways so meh.

[jloundy]

yeah, dos applications are quiet boring, but thats where most people start

[fauntleroy42]

helios is right... none of the system commands anyone has posted so far in the forums works when I run their code on my terminal. Printing 50 lines may be grossly inelegant, but at least it works on all platforms.

[Duthomhas]

Sigh.

Here are the two OS-specific ways to do it on 90% (made-up statistic) of all platforms.
http://www.cplusplus.com/forum/articles/10515/page1.html#msg49080

All it takes is some proper macro branches to account for your hardware

#if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__TOS_WIN__) || defined(__WINDOWS__)

  /* This here be the Windows method */

  #ifndef __WIN32__
    #define __WIN32__
  #endif

  #include <windows.h>

  void ClearScreen()
    {
    ...
    }

#elif defined(unix) || defined(__unix) || defined(__unix__)

  /* And this is the POSIX method.
   * Keep in mind that not all compilers #define one of the above macros.
   * You're compile script will have to make sure it is #defined before compiling.
   */

  #include <unistd.h>
  #include <term.h>

  void ClearScreen()
    {
    ...
    }

#else

  /* And if you are not using Windows or POSIX
   * but some weird, ancient system like a VAX.
   */

  #ifdef __cplusplus__

    #include <iostream>
    #include <string>

    void ClearScreen()
      {
      cout << string( 100, '\n' );
      }

  #else

    #include <stdio.h>

    void ClearScreen()
      {
      int n;
      for (n = 0; n < 10; n++)
        printf( "\n\n\n\n\n\n\n\n\n\n" );
      }

  #endif

#endif 

This is just a simple, one-file example. It is normal for large projects to have OS-specific files for doing things (like clearing the screen), and an appropriate makefile for each architecture, where the correct files are #included and linked to the executable.

Hope this helps.

[helios]

What about MacOS <10?

[Duthomhas]

A system that has no console?

[helios]

It doesn't? I would have assumed it did, but I don't really know.

[chrisname]

Thanks for the help.

The reason I printed fifty spaces several times was because I'm never going to have printed > 50 lines. At most, I'll have used 20. Usually I clear after every time I start something new - example: If there was a level in a game I would clear the screen after every 'checkpoint' in the level and at the beginning and end of each level. I wouldn't use so much text that they'd have to scroll down.