ref: 23620bb1dbbf80f07a156d3f1fe1e74d5f4d61ba 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; }