ref: cf9a3c2ad5a1e1a371cad0b6d5fc4164a68caf76 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; }