ref: 6361c0a2f202ae56f70cb4a7e8b6f45d54abe1e8 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; }