ref: abf8a2b5e3deff0a2b1b29b0bfb86f22d874f9b5 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; }