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From "McRoy, Jeffrey (GE Healthcare)" <>
Subject Re: Working with pipes
Date Fri, 23 Feb 2018 20:57:08 GMT
Ah, ok. I did not do the following from the Guac server:


$ ./guacctl -o "test-pipe"; echo -n "hello world"; ./guacctl -c


I thought the pipe would be available as part of the SSH or Telnet connection being established
and the text coming from the connected device would be available in the pipe. I was hoping
to access the text data at the javascript level.





From: Mike Jumper <>
Reply-To: "" <>
Date: Wednesday, February 21, 2018 at 2:07 PM
To: "" <>
Subject: EXT: Re: Working with pipes


Yes, onpipe should be firing for pipe streams created in this way. To demonstrate general
usage and expectations here, I've created a quick topic branch to act as a temporary POC which
adds handling for "text/plain" pipe streams, logging their creation, closure, and any data
received along the stream:


After establishing an SSH connection via a Guacamole server having the above commit, I ran
the following one-liner to open a new pipe stream called "test-pipe", print "hello world"
while output is redirected to that pipe stream, and finally close the stream:


    $ ./guacctl -o "test-pipe"; echo -n "hello world"; ./guacctl -c


The log within the browser displayed:


    pipe: test-pipe: stream begins

    pipe: test-pipe: "hello world"

    pipe: test-pipe: stream ends


and withing guacd:



    guacd[3374]: DEBUG: Terminal output now redirected to pipe 'test-pipe'.

    guacd[3374]: DEBUG: Terminal output now redirected to display.



- Mike



On Wed, Feb 21, 2018 at 6:48 AM, McRoy, Jeffrey (GE Healthcare) <>

If the Guac server is opening a pipe stream and redirecting output to it, wouldn’t the onpipe
event fire in the Guac client?


guacClient.onpipe = function(input_stream, mimetype, name) {

                reader = new Guacamole.StringReader(input_stream);

                reader.ontext = function receiveText(text) {








From: Mike Jumper <>
Reply-To: "" <>
Date: Tuesday, February 20, 2018 at 9:33 PM
To: "" <>
Subject: EXT: Re: Working with pipes


On Tue, Feb 20, 2018 at 7:23 PM, Nick Couchman <> wrote:

Is it possible for the client to access the terminal output at either the javascript or java



So, one thing to keep in mind, here, is that the terminal output from SSH and Telnet is transmitted
from guacd to the Guacamole Client as an image, not as text.  I know it doesn't *seem* like
it, particularly since the client allows you to select text and copy it to the clipboard (and
vice-versa), but if you look at the actual data going back and forth, all of the screen output,
include "text" from the terminal, is image data.  So, doing anything with it (parsing, etc.)
at the JavaScript layer is probably impractical, if not impossible.


Waaaaaait! Guacamole does send images, yes, but there is also an OSC which temporarily redirects
output to a pipe stream:


There is an example of this within guacctl:


- Mike



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