ref: 49f1b55b7a3ddc7bb97a53ab70fc3e88e3a897aa dir: /sys/src/ape/lib/ap/gen/abs.c/
#include <stdlib.h> int abs(int a) { if(a < 0) return -a; return a; } long labs(long a) { if(a < 0) return -a; return a; }