ref: 6bd7215355f1a2aa90c6166d3b2b6dae1f0711c2 dir: /sys/src/libc/port/abs.c/
#include <u.h> #include <libc.h> int abs(int a) { if(a < 0) return -a; return a; } long labs(long a) { if(a < 0) return -a; return a; }