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From: Flori on 20 Jan 2010 07:09 I need Google protocol-buffers <http://code.google.com/p/protobuf/> for communication in our current project and was disappointed to see that there seems to be no Tcl language-binding (but for many other languages there is). Since the en-/de-coding is simple <http://code.google.com/intl/de/apis/ protocolbuffers/docs/encoding.html>, I just wanted to do it myself. But then I was disappointed again, because to correctly implement it in Tcl I have to read bytes from a channel not chars and there seems to be no way to accomplish this in Tcl! Do I really have to descend to C? Shouldn't we have a way to read bytes from a channel in plain Tcl? Any suggestions? regards, Florian
From: Arjen Markus on 20 Jan 2010 07:52 On 20 jan, 13:09, Flori <Florian_M...(a)yahoo.de> wrote: > I need Google protocol-buffers <http://code.google.com/p/protobuf/> > for communication in our current project and was disappointed to see > that there seems to be no Tcl language-binding (but for many other > languages there is). > Since the en-/de-coding is simple <http://code.google.com/intl/de/apis/ > protocolbuffers/docs/encoding.html>, I just wanted to do it myself. > But then I was disappointed again, because to correctly implement it > in Tcl I have to read bytes from a channel not chars and there seems > to be no way to accomplish this in Tcl! > > Do I really have to descend to C? > Shouldn't we have a way to read bytes from a channel in plain Tcl? > > Any suggestions? > regards, > Florian Have you setting the channel options to translation binary (via fconfigure)? Regards, Arjen
From: miguel sofer on 20 Jan 2010 07:57 Flori wrote: > But then I was disappointed again, because to correctly implement it > in Tcl I have to read bytes from a channel not chars and there seems > to be no way to accomplish this in Tcl! > > Do I really have to descend to C? > Shouldn't we have a way to read bytes from a channel in plain Tcl? > > Any suggestions? Look at chan configure $chan -translation binary http://www.tcl.tk/man/tcl8.5/TclCmd/chan.htm
From: Eric Hassold on 20 Jan 2010 07:59 Le 20/01/2010 13:09, Flori a �crit : > I need Google protocol-buffers<http://code.google.com/p/protobuf/> > for communication in our current project and was disappointed to see > that there seems to be no Tcl language-binding (but for many other > languages there is). > Since the en-/de-coding is simple<http://code.google.com/intl/de/apis/ > protocolbuffers/docs/encoding.html>, I just wanted to do it myself. > But then I was disappointed again, because to correctly implement it > in Tcl I have to read bytes from a channel not chars and there seems > to be no way to accomplish this in Tcl! > > Do I really have to descend to C? > Shouldn't we have a way to read bytes from a channel in plain Tcl? > Hello, Yes, we should...and we have. fconfigure $chan -translation binary -encoding binary set buf [read $chan $nbytes] then buf is a byte array. Use [binary] command to parse it, or string operations, since EIAS, including bytearrays. Eric
From: Alexandre Ferrieux on 20 Jan 2010 08:41
On Jan 20, 1:09 pm, Flori <Florian_M...(a)yahoo.de> wrote: > > in Tcl I have to read bytes from a channel not chars and there seems > to be no way to accomplish this in Tcl! I wonder where you got that myth. Google may be biased towards Python, they are everything but idiots. Disinformation must come form elsewhere... By the way, thanks for the heads-up on protobuf, never heard of it before. While the protocol is thoroughly described and rather simple, the encoding of varints, the zigzag mapping, etc. don't strike me as the most machine-efficient thing ever. Of course you're saving bytes here and there, but the need to shuffle bits at every corner costs you cycles. I don't predict a world domination by protobuf too soon ;-) -Alex |