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 How to read router prompt and use it?
#1
When i login to a router, i get a following prompt.

R3-NYC
login: tac
Password:
[Router]R3-NYC#
[Router]R3-NYC#show clock
Wed May 22 04:46:18 2019 CST
[Router]R3-NYC#

1. How to capture CLI prompt to a string variable and use it for read_until() ?
i want to capture the prompt "[Router]R3-NYC#" . If i use read_until(), i have to mention the match. But i want to capture it after i login and use it later for the read_until() function the entire string instead of partial matches. I cannot hard core the hostname because i use this function for several other devices which will have different prompts.

2. How to capture command output to a string ?
I saw many refering to the function read_eager(). For some reason, when i test it, it has no capture. Only read_all() is working as expected. For this i have to wait till the telnet is closed. Could you please share some examples, if read_eager() is working for you.

Thanks
Simbha
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#2
Took a while but i could figure it out. Just in case any one is interested.

==== skipped the tn connect part===

Prompt capture to a string:
>>>tn.write(b" " + "\n".encode('ascii'))   ===> Send a simple enter("\n" character and capture the output to get prompt.
>>>str2 = tn.read_eager().decode()   ====> Save prompt to a string.
>>>print(str2)
Output:
[Router]R5-NYC#
Command output capture to a string in case output is multiple lines.
>>>tn.write(b"show clock" + "\n".encode('ascii'))
>>>str2 = tn.read_very_eager().decode()
>>>print(str2)
Output:
show clock Wed May 22 07:16:09 2019 CST [Router]R5-NYC#
tn.read_eager() ===> Kinda returns line by line output but very inconsistent and can be saved to a string.
tn.read_very_eager() === > Returned the entire output(including multiple lines) and can be saved to a string.
Yoriz wrote May-06-2019, 08:33 AM:
Please post all code, output and errors (in it's entirety) between their respective tags. I did it for you this time, Here are instructions on how to do it yourself next time.
Please mark your thread as solved when you resolve your original problem. More info here
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