Provided by: allegro5-doc_5.2.8.0+dfsg-1_all 
NAME
al_fixsqrt - Allegro 5 API
SYNOPSIS
#include <allegro5/allegro.h>
al_fixed al_fixsqrt(al_fixed x)
DESCRIPTION
This finds out the non negative square root of x. If x is negative, Allegro’s errno is
set to EDOM and the function returns zero.