Redirect the output of "ssh -T [email protected]"

Question

I am attempting to check the output of running the command "ssh -T [email protected]"

The output should look like:

Hi xyz! You've successfully authenticated, but GitHub does not provide shell access.

However, I am unable to capture this output. Where is this text coming from and how can I access it so I can test against it?

Piping the output or writing to a file yields no results.

ssh -T [email protected] | grep "successful"

Grep here receives no input.

try `ssh -T [email protected] 2>&1| grep successful`. Good luck. — shellter, Jul 20 '19 at 02:52
Thank you @shellter! And for other people arriving who will probably have the same next question as me: https://stackoverflow.com/questions/818255/in-the-shell-what-does-21-mean — Ampix0, Jul 20 '19 at 04:07
@shellter, can you add the same as an answer so that ampix can accept it. It will mark the question as answered. — Mihir Luthra, Jul 20 '19 at 05:59

score 1 · Accepted Answer · answered Jul 20 '19 at 13:01

1

Error messages are usually written to a separate "stream" called StdErr.

You can redirect the StdErr output to be merged with the StdOut (output).

[email protected] 2>&1 | grep "successful"

Will solve your problem.

2>&1 
|| |
|| +-> 1 is the filehandle num assosciated with stdin
|+---> >& redirects from left to right, "merging" the 2 specified streams 
+===-> 2 is the filehandle number for stderr

answered Jul 20 '19 at 13:01

shellter

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@Ampix0 : See my full answer to your Q about `ssh` ;-). – shellter Jul 20 '19 at 13:05
@Mihir : Per your request. `ssh` comment turned into an answer ;-) – shellter Jul 20 '19 at 13:05

Redirect the output of "ssh -T [email protected]"

1 Answers1