Creates and returns a new thread of control.
The optional name
provides a convenient
way of referring to the thread to the user. If not supplied, the name
defaults to "thread".
The optional group
allows the new thread to be created as a
member of a thread group other than the current thread group. Since
a thread's group cannot be changed once created, this is the only
way to create a thread running in a different group.
The newly created thread is initially suspended, with a suspend count of 1. Use thread-resume to make the thread available for execution.
The behavior of the thread is to invoke the given thunk
. When
thunk
returns, the thread enters the complete state and
thread-join returns (all) the values returned by thunk
.