ref: a7f1bb9a9e1720b22d1fbed16e7527fa2cd0d82c 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; }