How to print a character using Shell script

Question

Below is my script that acquire the MAC of the machine and store within a config file.

My problem is that within each line have the character " " and it dont print it inside the file, how can I write the file using " "

MAC=$(ifconfig eth0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}')
echo "
view.sslVerificationMode = *3*
view.autoConnectDesktop = *TRUE*
view.autoConnectBroker = *TRUE*
view.kioskLogin = *TRUE*
view.nonInteractive = *TRUE*
view.fullScreen = *TRUE*
view.nomenubar = *TRUE*
view.defaultBroker = *viewcs*
view.defaultUser = *CM-${MAC//:/_}*
" > /etc/vmware/view-mandatory-config;
sed -i 's/*/"/g' /etc/vmware/view-mandatory-config

Answer 1

with cat and a here-doc you can use multi-line input without escaping charaters

MAC=$(ifconfig eth0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}')
cat << EOT > /etc/vmware/view-mandatory-config
view.sslVerificationMode = "3"
view.autoConnectDesktop = "TRUE"
view.autoConnectBroker = "TRUE"
view.kioskLogin = "TRUE"
view.nonInteractive = "TRUE"
view.fullScreen = "TRUE"
view.nomenubar = "TRUE"
view.defaultBroker = "viewcs"
view.defaultUser = "CM-${MAC//:/_}"
EOT

cat will relay the stdin input generated by the here document to stdout, thus enabling redirection to a file

Answer 2

Simply escape double-quotes within the outer double-quotes by putting a backslash in front of them:

MAC=$(ifconfig eth0 | grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}')
echo "
view.sslVerificationMode = \"3\"
view.autoConnectDesktop = \"TRUE\"
view.autoConnectBroker = \"TRUE\"
view.kioskLogin = \"TRUE\"
view.nonInteractive = \"TRUE\"
view.fullScreen = \"TRUE\"
view.nomenubar = \"TRUE\"
view.defaultBroker = \"viewcs\"
view.defaultUser = \"CM-${MAC//:/_}\"
" > /etc/vmware/view-mandatory-config