ref: 056eb9f7d8b1a577f7029e3d0e6d40cf6c2e86b0 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; }