ref: 015f7f51129c6cddac5d9e8bd66a4c8a2dbb87e8 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; }