Re: [ns] link handles

[Patrick Simen <psimen@eecs.umich.edu>]

Thanks, but . . . all my other simulations (which work) have used duplex
links.  How could they work?  --Pat.

On Mon, 19 Jun 2000, Haobo Yu wrote:

> There is no duplex link objects in ns. Use Simulator::link{} to get a
> handle of a particular simplex link (n0, n1). See tcl/lib/ns-lib.tcl to
> find this function.
> 
> On Mon, 19 Jun 2000, Patrick Simen wrote:
> 
> > Date: Mon, 19 Jun 2000 21:19:36 -0400 (EDT)
> > From: Patrick Simen <psimen@eecs.umich.edu>
> > To: ns-users@ISI.EDU
> > Subject: [ns] link handles
> > 
> > I am trying to vary a link's bandwidth and delay dynamically.  I came
> > across Sally Floyd's email
> > (http://www-mash.CS.Berkeley.EDU/dist/archive/ns-users/0005/0409.html) about
> > her changes to ns which allow this, but only after trying lots of stuff
> > with links.
> > 
> > This brought up a question about whether the info in the ns manual,
> > chapter 6.4, is
> > correct.  It gives a list of commands that begin with "$ns_".  That seems
> > to work.  But it also lists commands like "$link up?".
> > 
> > I can't get those to work.  How do you get a handle to a link object? I
> > wrote:
> > 
> > set newlink [$ns duplex-link $n1 $n2 1Mb 10ms DropTail]
> > 
> > But then the command "$newlink up?" fails.  The failure message is:
> > 
> > invalid command name ""
> >     while executing
> > "$newlink up?"
> > 
> > And when I write: "puts stdout $newlink", I just get a blank line, as if
> > no handle to the link between $n1 and $n2 exists.  So how do you get a
> > handle for a link?  Or, what does "$link" refer to in chapter 6.4?
> > 
> > --Pat.
> > 
> > ---------------------- 
> > Patrick Simen 
> > psimen@eecs.umich.edu 
> > EECS Dept.
> > University of Michigan 
> > ----------------------
> > 
> > 
> > 
> 
> 

----------------------
Patrick Simen
psimen@eecs.umich.edu
EECS Dept.
University of Michigan
----------------------