ref: a509e8b29634aeb5d2a71999c03a24f6c89bd836 dir: /sys/src/ape/lib/bsd/setlinebuf.c/
#include <stdio.h> void setlinebuf(FILE *f) { static char buf[BUFSIZ]; setvbuf (f, buf, _IOLBF, BUFSIZ); }