fs.fstat(fd[, options], callback)
fd<integer>options<Object>callback<Function>err<Error>stats<fs.Stats>
fd<integer>options<Object>callback<Function>err<Error>stats<fs.Stats>
Asynchronous fstat(2). The callback gets two arguments (err, stats) where
stats is an fs.Stats object. fstat() is identical to stat(),
except that the file to be stat-ed is specified by the file descriptor fd.