I am writing a shell script that automates the installation of a certain software tool. The problem is that the installer requires the users to enter some options during installation, so this requires me to watch the script while running. My question is can I send these options from the script directly without the need to manually enter them.

If you know the input to the installer, you can: 1) place the input in a file and redirect it to the installer: installer < input 2) call the installer using a unix here document: installer << MSG your input goes here MSG

Hello, Whats a Unix here document. Can you help me a bit with that. Vibhor Kumar Agarwal

A unix document allows you to redirect standard input from the key board to lines in your shell script. You have to use the I/O redirection operator followed by an arbirary delimiter word. The input lines start after the CR that follows the delimiter and continue up to the 2nd delimiter word. This delimiter is on a line all by itself. Let's look at an example. Consider when you prompt the user for input: echo "enter x" read x echo "x is: $x" Here's an example of a unix here document: echo "enter y" read y << MSG whatever MSG echo "y is: $y" # make sure there's no white space after # the delimiter MSG. In the above example, variable y is automatically assigned the value: whatever - from the script. Another typical use of a here document is replacing a block of echos: echo "this is line 1" echo "this is line 2" echo "this is line 3" # here document: cat << HERE this is line 1 this is line 2 this is line 3 HERE You can ever embed shell variables in here documents: x=whatever cat << HERE Enter a shell variable $(echo $x) HERE

Thank you, using here documents solved my problem.