ref: aedb35af2c5defe2ede15f4e5a7bffe8a3bc32bc dir: /sys/src/ape/lib/bsd/setlinebuf.c/
#include <stdio.h> void setlinebuf(FILE *f) { static char buf[BUFSIZ]; setvbuf (f, buf, _IOLBF, BUFSIZ); }