Assigning output to variable in automated chroot script

Question

For the life of me, I cannot figure out how to chroot through a script, and assign a value to a variable. Okay, so I learned how to chroot and execute commands from a script without halting the flow of the script:

#!/bin/bash
# Mini script for chrooting into chroot_dir and executing commands.

chroot_dir=$1
cat << EOF | chroot $chroot_dir /bin/bash
sysname=\`hostname\`
echo "You are running script.sh on ${sysname}"
EOF

Running this script, ./script.sh "/chroot_dir/", I get the following output:

You are running script.sh on

It seems like either sysname never gets assigned, or sysname loses its value immediately. How do I assign a value to sysname using this method to chroot?

Answer 1

The reason is that ${sysname} gets evaluated when the script is read, rather than when later executed. If you put a backslash (\) before the dollar ($) it should work better. Note that it has nothing to do with chroot, but it rather is a feature of bash.