Pg 44:
-for "wait who gets done first", tc.wait() should have parameter "Any" because default is "All"
-what is the purpose of "buf=buf1;", seeing that buf is never read and is re-written in each loop pass?
-on each "create a new read task" inside the loop, the new task should also be put into tmap (if my understanding is 
correct, i.e. the read() method constructs a new task object each time)
-on "skip for stream type", NULL is passed as the output buffer, but the specification of saga::stream::read does not 
allow this