Regarding Telnet library in python

[Hishaam]

Hi,

In python documentation, i found a telnet example as follows:

-------------------------------------------------------------------------
import getpass
import sys
import telnetlib

HOST = "localhost"
user = raw_input("Enter your remote account: ")
password = getpass.getpass()

tn = telnetlib.Telnet(HOST)

tn.read_until("login: ")
tn.write(user + "\n")
if password:
tn.read_until("Password: ")
tn.write(password + "\n")

tn.write("ls\n")
tn.write("exit\n")

print tn.read_all()
-------------------------------------------------------------------------

The ouput of it as follows:

-------------------------------------------------------------------------
Enter your remote account: root

Last login: Mon Aug 13 11:54:32 from pcp246879pcs.ca
Sun Microsystems Inc. SunOS 5.10 Generic January 2005
# Desktop boot hishaam net system work
Documents cdrom home opt tfile2 zonemgr
File.txt dev kernel platform tmp
QA_tmp devices lib proc usr
acunix etc lost+found sbin var
bin export mnt sfile vol
#

-------------------------------------------------------------------------

The difficulty i find in this is th code line "print tn.read_all()" is
used for reading all of the output of the code at once.

Is there a possibility to read the stdout of each command by command
like -

# ls
<stdout 1>
[capture <stdout 1> in a variable]
# cd /root
<stdout 2>
[capture <stdout 2> in a variable]


Like the above would be useful if there are a large number of commands
to be executed in the telnet session.

Can anyone help on this?

Regards,
Hishaam

 

[Eddie Corns]

Hi,

In python documentation, i found a telnet example as follows:

HOST = "localhost"
user = raw_input("Enter your remote account: ")
password = getpass.getpass()

tn = telnetlib.Telnet(HOST)

tn.read_until("login: ")
tn.write(user + "\n")
if password:
tn.read_until("Password: ")
tn.write(password + "\n")

print tn.read_all()
-------------------------------------------------------------------------

The ouput of it as follows:

Last login: Mon Aug 13 11:54:32 from pcp246879pcs.ca
Sun Microsystems Inc. SunOS 5.10 Generic January 2005
# Desktop boot hishaam net system work
Documents cdrom home opt tfile2 zonemgr
File.txt dev kernel platform tmp
QA_tmp devices lib proc usr
acunix etc lost+found sbin var
bin export mnt sfile vol
#

The difficulty i find in this is th code line "print tn.read_all()" is
used for reading all of the output of the code at once.

Is there a possibility to read the stdout of each command by command
like -

# ls
<stdout 1>
[capture <stdout 1> in a variable]
# cd /root
<stdout 2>
[capture <stdout 2> in a variable]

Like the above would be useful if there are a large number of commands
to be executed in the telnet session.

Can anyone help on this?

Regards,
Hishaam

One way of doing this is to send the commands one at a time and do: (untested)

prompt = '\n# '

tn.write("ls\n")
stdout = tn.read_until(prompt)
for line in stdout.splitlines():
...
etc.

alternatively just send them all in one go as you have been and save the
output in a variable and split that on the prompt. In either case you may
want to change the prompt to something easier to match on like "$hostname# ".

Eddie