Get more data from the pipe. The parameter indicates the desired number
of elements to add to the end of the window. If 0 is passed, then it is
up to the implementation of the pipe to determine the optimal number of
elements to add.
The number of elements added. This can be less than or more
than the parameter, but will only be 0 when no more elements
can be added. This signifies EOF.
Get more data from the pipe. The parameter indicates the desired number of elements to add to the end of the window. If 0 is passed, then it is up to the implementation of the pipe to determine the optimal number of elements to add.