Progress bar

[JFonseka]

Is there anyway to get a progress bar in a console application like Cygwin??
If not, is it possible to at least get a percentage runner. like whenever a task is done, the percentage is updated, a better implementation than:

if () {
 
    printf("10%\n");
 
}

if() {

   printf("20%\n");

}

[vart]

int x;
for(x = 0; x<100; x++)
{
   printf("\b\b&#37;02d%%",x);
   Sleep(1000);
}

[JFonseka]

what is \b ? and also what library do i need to include for 'sleep' ?

[JFonseka]

Nvm I got that running, but it's doing nothing...I changed it from 1000 to 10 and still it does nothing :S

[slingerland3g]

Not sure why the use of sleep here. Try this. You can even place this in its own function if you like

int x;
    
    double numtasks = 76;
    double taskcompleted = 10;
    
    double percentage = (taskcompleted / numtasks) * 100;
    
    for(x = 0; x < percentage; x++)
    {
        printf("|");
           
    }
       printf(" &#37;.2f%%\n", percentage);
    return (EXIT_SUCCESS);

[matsp]

You may also find that printf() is buffering if you don't use "\n" on the end of the string, which means that you need fflush(stdout) to force the printed stuff to be shown on the console.

Using '\r' instead of '\b' will take the cursor to the beginning of the line no matter how long it is (which is useful for example if you want to show what file is being copied when copying a bunch of files, etc).

--
Mats

[vart]

Here is the working example

#include <stdio.h>
#include <windows.h>
int main(void)
{
	int x;
	for(x = 0; x<100; x++)
	{
	   printf("\b\b\b&#37;02d%%",x);
	   Sleep(1000);
	}
}

windows.h is for Sleep
Sleep is for emulating delay between sequential printf

\b removes last printed character

[slingerland3g]

You may also find that printf() is buffering if you don't use "\n" on the end of the string, which means that you need fflush(stdout) to force the printed stuff to be shown on the console.

Using '\r' instead of '\b' will take the cursor to the beginning of the line no matter how long it is (which is useful for example if you want to show what file is being copied when copying a bunch of files, etc).

--
Mats

Thanks for the hint on '\r' and fflush! Was interested in this as well. So thought I would have a try at this code. Below works pretty well.

#include <stdio.h>
#include <stdlib.h>

int show_status (double x);

int main()
{
    int taskcompleted = 0;
    double numtasks = 76;
         
    for(; taskcompleted <= numtasks; taskcompleted++)
    {
       show_status((taskcompleted / numtasks) * 100);
    }
    
   return (EXIT_SUCCESS);    
    
}

int show_status (double percent)
{
    int x;
    for(x = 0; x < percent; x++)
    {   
       printf("|");
              
    }
       printf("%.2f%%\r", percent);
       fflush(stdout);
       system("sleep 1");
      
    
    return(EXIT_SUCCESS);
}

[JFonseka]

Thanks for all that guys, interesting stuff

[dwks]

Note: printing a '\b' is like typing backspace, except the character isn't erased. If you want it to be erased, you can use something like this:

printf("\b \b");

The space writes over whatever character was printed there previously.

Another thing: if you print \r after some text, then something else printed later could overwrite it. In other words, something like this looks strange:

printf("Hello, World!\r");
printf("Error\n");

In general, I find it's better to print the \r first:

printf("\rHello, World!");

This method also has the advantage that the cursor appears after the text, as you'd expect, rather than at the beginning of the line.

Also note that neither '\b' nor '\r' can go back a line. Once you print a newline ('\n'), you can no longer edit that line.

Finally, here's my stab at it:

#include <stdio.h>
#include <time.h>

void twirlybar(void) {
    static clock_t last = 0;
    static const char *dir = "|/-\\";
    static size_t angle = 0;
    clock_t now;
    
    now = clock();
    if((now - last) / (CLOCKS_PER_SEC / 10.0) >= 0.5) {
        if(++angle == sizeof(dir)/sizeof(*dir)) angle = 0;
	last = now;
    }

    putchar('\b');
    putchar(dir[angle]);
    fflush(stdout);
}

int main(void) {
    for(;;) twirlybar();

    return 0;
}

(Code highlighted with codeform.) Of course, it would be better to use time_t in a real application, because clock() might be called by something else. And there are far too many static variables in it, passing them in would be a better idea . . . .