ref: 7fa5db9d6a8d3b7d1430cab7df9fda9b8ee1ec0b dir: /sys/src/ape/lib/ap/plan9/fsync.c/
#include <sys/types.h> #include <unistd.h> #include <errno.h> int fsync(int) { errno = EINVAL; return -1; }