Loop through file and send commands over expect - bash

Question

I am trying to send commands from a file to a device over expect. I tried sending them one at a time from my local machine but all of my file paths were relative to local, not relative to the remote device. My solution was to try to upload the file to the device and load the commands from there. When I try to load the file I keep getting a permissions issue even though if I cat the file from the device I don't have a problem reading it. The file has 1 command per line.
devicepath=rsync://root#localhost:$PORT_RSYNC/root/var/root/file.txt
/usr/bin/rsync -Pavr $1 $devicepath
expect <<- expect_feed
set send_slow {1 .001}
spawn ssh -o NoHostAuthenticationForLocalhost=yes -p $PORT_SSH root#localhost
expect -re "password:"
send -s "password\r"
expect -re $PROMPT_ROOT
send -s "chmod 777 /var/root/file.txt\r"
expect -re $PROMPT_ROOT
set f [cat /var/root/file.txt]
set cmds [split [read $f] "\n"]
close $f
foreach line $cmds {
send -s "$line\r"
expect -re $PROMPT_ROOT
expect_feed
This yields:
root# cat: /var/root/file.txt: Permission denied
I also tried
set f [open /var/root/file.txt]
...but it gave the same error.

Answer 1

If the file you send over contains shell commands, treat it as such and simply source it on the remote host
devicepath=rsync://root#localhost:$PORT_RSYNC/root/var/root/file.txt
/usr/bin/rsync -Pavr "$1" "$devicepath"
export PROMPT_ROOT PORT_SSH
expect << 'EXPECT_FEED'
set send_slow {1 .001}
spawn ssh -o NoHostAuthenticationForLocalhost=yes -p $env(PORT_SSH) root#localhost
expect -re "password:"
send -s "password\r"
expect -re $env(PROMPT_ROOT)
send -s ". /var/root/file.txt\r" ;# <<<<
expect -re $env(PROMPT_ROOT)
send "exit\r"
expect eof
EXPECT_FEED
I prefer to use quoted heredocs: shell variables can be passed to expect via the environment.
I'm assuming root's shell is a POSIX-type shell where . is the "source" command.

Answer 2

Thanks for the great suggestions. It is working like this.
It would probably work just as well without send slow now that it is sending one line at a time and waiting for a response.
The last command in the file is 'quit' in order to return to the root prompt, I suppose that could have been hard coded
cmdpath=$1
export cmdpath
expect << 'EXPECT_FEED'
set send_slow {1 .001}
set commandfile [open $env(cmdpath)]
spawn ssh -o NoHostAuthenticationForLocalhost=yes -p $env(PORT_SSH) root#localhost
expect -re "password:"
send -s "password\r"
expect -re $env(PROMPT_ROOT)
send -s ">the name of the process accepting commands<\r"
while { [gets $commandfile line] != -1 } {
expect -re $env(PROMPT)
send -s "$line\r" }
expect -re $env(PROMPT_ROOT)
send "exit\r"
expect eof
EXPECT_FEED