alert (3) - Linux Manuals
alert: Displays a popup alert box. Allegro game programming library.
NAME
alert - Displays a popup alert box. Allegro game programming library.SYNOPSIS
#include <allegro.h>
int alert(const char *s1, *s2, *s3, const char *b1, *b2, int c1, c2);
DESCRIPTION
Displays a popup alert box, containing three lines of text (s1-s3), and with either one or two buttons. The text for these buttons is passed in `b1' and `b2' (`b2' may be NULL), and the keyboard shortcuts in `c1' and `c2' as ASCII value. Example:
if (!exists(CONFIG_FILE)) alert(CONFIG_FILE, "not found.", "Using defaults.", "&Continue", NULL, 'c', 0);