Bash variable with the content of a file

NTPFILECONTENT=$(cat /etc/chrony.conf)

This will store the ‘\n’ characters as well.

Display bash variable with the content of a file

echo "${NTPFILECONTENT}"

Beware the quotes

Append content to a bash variable with a new line

NTPFILECONTENT="${NTPFILECONTENT}"$'\n'"pool ${ntp} iburst"

Create files with heredocs

cat << EOF > /your/file
mycontent
  even with spaces
EOF

Some details:

• You can use EOF or whatever you want.
• The EOF needs to be as it is, no whitespace before it.

• If you don’t want to interpret variables in the text, use single quotes such as:

  cat << 'EOF' > /your/file
  ...
  EOF
  

• In a shell script with tabs such as:

  #!/usr/bin/env bash
  
  if true ; then
  cat << EOF > /tmp/yourfilehere
  my content
  EOF
  fi
  

you better use <<- EOF to disable leading tabs to make the code more readable:

#!/usr/bin/env bash

if true ; then
    cat <<- EOF > /tmp/yourfilehere
    mycontent
    EOF
fi

NOTE: You need to use tabs.

References: * https://stackoverflow.com/a/2954835 * http://tldp.org/LDP/abs/html/here-docs.html