I am working on capturing lines of output from a korn script that is used to import optical disks into a jukebox. The script is running on Solaris 8. Insertdiscs calls the binary named vimport which starts up and prompts for a disk to be inserted. I am able to capture output with this line below which would be perfect except that as soon as insertdiscs is piped to tee (as opposed to running it alone) I need to hit enter twice to get it to start vimport (see below) for each loop.
#!/bin/bash
#In Solaris 8 only bash handles the below process substitution properly.
insertdiscs | tee >(egrep Imported\|INFO >> /tmp/importdisclog.txt)
I have tried
printf "\n" | insertdiscs | tee >(egrep Imported\|INFO >> /tmp/importdisclog.txt)
as well as piping from echo "\n" and all that gets me is infinite new lines at every prompt from the interactive vimport script.
This is the insertdiscs script that is called from my code above:
#!/bin/ksh
while [ $TRUE ]
do
vimport -j 1
rc=$?
if [ $rc -eq 0 ]; then
log_message "G" "Volume import succeeded for jukebox using insertdiscs."
else
log_message "B" "Volume import failed for jukebox using insertdiscs."
fi
done
The shells do no seem to support this very well.
Normally I would do this kind of tasks with expect.
My experience is that one has to mimic the time behavior of the program that
expects something from standard input.
You may try replacing the simple printf by this subshell expression:
Thanks hfreyer. I don't think I described the problem very well. Basically my insertdiscs script calls the vimport binary in a loop which is always running in a terminal. vimport is an interactive program that prompts to insert magnetic optical disks in a jukebox one at a time (enter slot number or hit enter at prompts for next available jukebox slot). The screen output for vimport has information that I need to also capture to a file (egrep Imported\|INFO). So in order to still see the interactive text from vimport to load disks and also capture parts of the output to file for processing I can start the script with:
insertdiscs | tee >(egrep Imported\|INFO >> /tmp/importdisclog.txt)
Except now I have to hit enter an extra time to get back to the beginning of the loop running vimport. Piping to tee adds the need for an extra enter key press. So I was hoping to somehow automatically add one enter key press or for some other solution. Otherwise the script always looks like it has hung when in fact it is ready to insert the next disk (after hitting enter an extra time to see the "please insert disk" prompt again).
Piping from print "\n" or (sleep 1; print "\n") sends too many newlines, I was hoping for some way to just send one if possible. Unfortunately the system is an old Sun box running Sun 5.8 so no expect.
After working on this issue for over a month. It looks the interactive vimport binary I am making a wrapper script for is using print -n or some equivalent to suppress new-lines in it's output so that user input appears on the same line. This is causing the need to type extra new lines and screwing up the flow of my script when piping the output to tee. Someone must have experienced this before. Any solutions?