Question

I want to connect to a remote host using telnet
there is no username/password verification
just

telnet remotehost

then I need to input some commands for initialization

and then I need to repeat the following commands:

cmd argument

argument is read from a local file, in this file there are many lines, each line is a argument
and after runing one “cmd argument”, the remote host will output some results
it may output a line with string “OK”
or output many lines, one of which is with string “ERROR”
and I need to do something according to the results.

basically, the script is like:

initialization_cmd  #some initial comands
while read line
do    
  cmd $line
  #here the remote host will output results, how can I put the results into a variable?
  # here I want to judge the results, like
  if $results contain "OK";then
       echo $line >>good_result_log
  else
       echo $line >> bad_result_log
  fi     
done < local_file

 the good_result_log and bad_result_log are local files

is it possible or not? thanks!

Answer 1

This won’t work as echo will output to the stdout of the tty and not to the stdin of the telnet process.

I would suggest writing an expect script for this task. Perhaps you could adapt something like this.