#include "graphics.h"
void showerrorbox(const char* message=NULL);
 

The showerrorbox function is available in the winbgim implementation of
BGI graphics. You do not need to include conio.h; just include
graphics.h. The function opens a windows error message box with the
specified message (or a standard message if the message parameter is
NULL). The message box waits for the user to click on OK button before
showerrorbox returns.
  See also
bgiout
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  Example
/* showerrorbox example */
#include "graphics.h"
 
int main(void)
{
   /* initialize graphics window at 400 x 300 */
   initwindow(400, 300);
 
   /* draw a line */
   line(0, 0, getmaxx(), getmaxy());
 
   /* display a sample error box */
   showerrorbox("Sample of an Error Box");
   closegraph();
   return 0;
}
 
 
 
 
==== Example of showerrorbox ====
<code c>
/* showerrorbox example */
#include "graphics.h"
 
int main(void)
{
   /* initialize graphics window at 400 x 300 */
   initwindow(400, 300);
 
   /* draw a line */
   line(0, 0, getmaxx(), getmaxy());
 
   /* display a sample error box */
   showerrorbox("Sample of an Error Box");
   closegraph();
   return 0;
}

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  no output of example at the moment
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