Asynchronously reads the entire contents of a file.
If options
is a string, then it specifies the encoding
.
The FileHandle
has to support reading.
If one or more filehandle.read()
calls are made on a file handle and then a filehandle.readFile()
call is made, the data will be read from the current position till the end of the file. It doesn't always read from the beginning of the file.