Open new gnome-terminal from scripts and input vars from present script. - linux

Question

#!/bin/bash
Dpath=/home/$USER/Docker/
IP=`sed -n 1p /home/medma/.medmadoc`
DockerMachine=`sed -n 2p /home/$USER/.medmadoc`
DockerPort=`sed -n 5p /home/$USER/.medmadoc`
DockerUser=`sed -n 3p /home/$USER/.medmadoc`
DockerPass=`sed -n 4p /home/$USER/.medmadoc`
if [ ! -d $Dpath ] ; then
mkdir -p $Dpath
else
stat=`wget -O ".dockerid" http://$IP/DOCKER-STAT.txt`
for ids in `cat .dockerid`
do
if [ "$ids" == "$DockerMachine" ] ; then
gnome-terminal -x sh -c 'sshfs -p$DockerPort $DockerUser#$IP:/var/www/html $Dpath ; bash '
nautilus $Dpath
zenity --info --text "Mounted $DockerMachine"
exit
else
:
fi
done
zenity --info --text "No Such ID:$DockerMachine"
fi
gnome-terminal -x sh -c 'sshfs -p$DockerPort $DockerUser#$IP:/var/www/html $Dpath ; bash '
this command opens up a new terminal but the problem is that it does not load vars like $DockerPort $DockerUser $IP $Dpath from this script.
How do I input the values in these vars from this script to the newly opened terminal ?
Thanks !

Answer 1

As indicated before, you could try to use double quotes instead of single quotes around the sshfs invocation.
Single quotes in Bash are used to delimit verbatim text, in which variables are not expanded. Double quotes, in contrast, allow for variables expansion and command substitution ($(...)) to take place.
If you do use double quotes, beware of unintended side-effects (your username may contain a space, a dollar, a semicolon, or any other shell-special character). A cleaner approach would be to export the variables to the environment before calling gnome-terminal (and not forgetting to add double quotes around your variables inside the single-quotes), so that your code looks like :
export Docker{Port,User} IP Dpath
gnome-terminal -x sh -c 'sshfs -p"$DockerPort" "$DockerUser#$IP":/var/www/html "$Dpath" ; bash'
You may not want to pollute the environment with variables that will only be used once. If that is the case, instead of exporting them, you can use Bash's declare -p feature to serialize variables before loading them into a new environment (in my opinion, this is the cleanest approach). Here is what it looks like :
set_vars="$(declare -p Docker{Port,User} IP Dpath)"
gnome-terminal -x bash -c "$set_vars;"'sshfs ....'
Using this latest method, the variables are only visible to the shell process that runs the sshfs command, not gnome-terminal itself nor any sub-process run thereafter.
PS: you could read all your variables at once from the ~/.medmadoc file by using the following code instead of repeated sed invocations :
for var in IP Docker{Machine,User,Pass,Port}; do
read $var
done < ~/.medmadoc
This code makes use of the read builtin, that reads a line of input into a variable (in its simplest form).
PPS: That stat variable probably won't contain any useful information, since the output of wget was redirected by the -O flag. Perhaps you meant to store the result code of wget into stat, in which case what you meant was :
wget -O .dockerid ...
stat=$?