clearing screens

[speve]

I am really new to C so have extremely limited knowledge at the moment. I am using a menu function in my program eg. if the user selects option 1 then it goes to that particular function, but I was wondering how you would clear the screen so the function appears at the top of the screen, just like when you first execute your program?

Thanks in advance!

Speve!

[zen]

Check the FAQ.

[iain]

new users should check the faq list first an dthe faq board, also list which environment you are programming in and which o/s you program for.

but check out clrscr()
or system calls (slow, but can work)

[Agrajag]

There is no way in ANSI C to clear the screen, because it would be horrible for ANSI to assume that the computer you are compiling C for even has a screen. Just think about it... how many mainframes do you know of with a screen? Anyways you have to find out the way that your compiler/system clears the screen which is different for almost every system that has a screen...
if all else fails get the screen size and output that many space characters (@ least that way it is portable)
The better way to do it though would be to use an abstraction layer. Write a function, lets say, foo() that clears the screen. Place it in a file called clrscr.c, and in the function have it call the correct function for that compiler and system and include that .c file in the project. Then you can call foo() to clear the screen, and make multiple clrscr.c files to go with your different compilers and systems. Also make sure you either make a clrscr.h file that includes a prototype for foo() or write a prototype for it in your program.

[beely]

hey... you could solve this problem by entering this system code. " system ("cls"); "

if you really know more about dos command, then i/m sure you could expert using system code. more example,

[ronin]

As long as the program is a 16 bit dos app this will work.

void cls();

void cls(void)
{
_asm
{
mov ah,02
mov bh,0
mov dx,0
int 10h

mov ah,9
mov cx,2000
mov bl,07h
mov al,' '
int 10h
}

return;
}

How it's called in your main

cls();

Try it in a win32 console app... just don't expect it to work.

[Agrajag]

beely while system("cls") may work in dos or windows, linux uses the command clear, so cls will not work in linux. Also system takes a very long time to call, and it would be significantly faster to output space characters to the screen, though it starts text at the bottom of the screen instead of the top like more traditional clear functions...

[bandw]

Jeeeeeezzzz, I dont know why you guys go forth and make it so bloody complicated. Theres an easy function for all you Noob programmers out there. Its called clrscr(); WOW!!! Just make sure you have included conio.h as a library and ur set :-)

So just remember...
#include <conio.h>

and the function
clrscr();

and you'll be sweet

[bobthefish3]

just to let you know, if you try and use the clrscr() function out of the conio.h header file, it may not work, because that is a compiler-specific function and is not ANSI, i know it works on a borland compiler, but it does not exsist on the microsoft compilers (unless you your self right the function -- which i would not attempt myself if i were you).

[klausi]

Hi!

You should only know your screen settings for it:

int count;
for(count=0;count<20;count++, putchar('')) ; /* e.g for 80*20 a screen */

klausi

[netboy]

About the conio.h header file, I heard that it is not supported in Linux system. This means that you won't be able to use the clrscr() function with the conio.h file if you are compiling under Linux...