#include <u.h>#include <libc.h>#include "authcmdlib.h" voiderror(char *fmt, ...){	char buf[8192], *s;	va_list arg; 	s = buf;	s += sprint(s, "%s: ", argv0);	va_start(arg, fmt);	s = vseprint(s, buf + sizeof(buf), fmt, arg);	va_end(arg);	*s++ = '\n';	write(2, buf, s - buf);	exits(buf);}