Unix create and use variables inside expect script - unix

Question

In my attempts to automatize access to a remote computer,
I am trying to create and use variables inside an expect script.
I am trying to do the following:
#!/bin/csh -f
/user/bin/expect<<EOF_EXPECT
set USER [lindex $USER 0]
set HOST [lindex $HOST 0]
set PASSWD [lindex $PASSWD 0]
set timeout 1
spawn ssh $USER#$HOST
expect "assword:"
send "$PASSWRD\r"
expect ">"
set list_ids (`ps -ef | grep gedit | awk '{ print $2 }'`)
expect ">"
for id in ($list_ids)
send "echo $id\r"
end
send "exit\r"
EOF_EXPECT
Several challenges with this code:
The ps | grep | awk line does not act as in the shell. It does not extract only the pid using the awk command. Instead, it takes the whole line.
The variable $list_ids is unrecognized although I set it using what I thought is variable setting inside expect script.
Lastly, how to do the for loop so that $id and $id_list will be recognized?
I am using csh. $env(list_ids) does not work for me, $env is undefined.

Answer 1

Both shell and tcl variables are marked with $. The contents of your here document are being expanded by your shell. You don't want that. csh doesn't have a value for $2 so expands it to the empty string and the awk command ends up becoming ps -ef | grep gedit | awk '{ print }'. Which is why you get the entire lines in the output.
You have your contexts confused here a bit. You need to escape the $ from the external csh if you want it to make it through to the embedded awk command. (Which is horrible but apparently the case for csh.)
In general you need to not try to merge csh and tcl commands/etc. like this it will greatly help you understand what is happening.
What do you mean "unrecognized"? Are you getting any other errors (like from the set command)?
I think you are looking for foreach:
$ tclsh
% foreach a [list 1 2 3 4] b [list 5 6 7 8] c [list a b c d] d [list w x y z]
puts "$a $b $c $d"
}
1 5 a w
2 6 b x
3 7 c y
4 8 d z
%
$env(list_ids) is a tcl variable. That csh doesn't know anything about it is unrelated to anything (well other than the problem in point one above so escape it). If you export list_ids in the csh session that runs the tcl script then $env(list_ids) should work in the expect script.
You don't want the () around the value in the set command either I don't think. They are literal there I believe. If you are trying to create a tcl list there from the (shell expanded) output from that ps pipeline then you need:
set list_ids [list `ps ....`]
But as I said before you don't really want to be mixing contexts like that.
If you can use a non-csh shell that would likely help here also as csh is just generally not good at all.
Also, not embedding an expect script inside a csh script would help if you can just write an expect script as the script file directly.

Answer 2

Reading here helped me a lot:
http://antirez.com/articoli/tclmisunderstood.html
The following lines do the trick, and answer all questions:
set list_ids [list {`ps -ef | grep gedit | awk '{print \$2 }'}]
set i 0
while {[lindex \$list_ids \$i] > 0} {
puts [lindex \$list_ids \$i]
set i [expr \$i + 1]
}