Have bash script answer interactive prompts [duplicate] - linux

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Passing arguments to an interactive program non-interactively
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Is it possible to have a bash script automatically handle prompts that would normally be presented to the user with default actions? Currently I am using a bash script to call an in-house tool that will display prompts to the user (prompting for Y/N) to complete actions, however the script I'm writing needs to be completely "hands-off", so I need a way to send Y|N to the prompt to allow the program to continue execution. Is this possible?

Answer 1

A simple
echo "Y Y N N Y N Y Y N" | ./your_script
This allow you to pass any sequence of "Y" or "N" to your script.

Answer 2

This is not "auto-completion", this is automation. One common tool for these things is called Expect.
You might also get away with just piping input from yes.

Answer 3

If you only have Y to send :
$> yes Y |./your_script
If you only have N to send :
$> yes N |./your_script

Answer 4

I found the best way to send input is to use cat and a text file to pass along whatever input you need.
cat "input.txt" | ./Script.sh

Answer 5

In my situation I needed to answer some questions without Y or N but with text or blank. I found the best way to do this in my situation was to create a shellscript file. In my case I called it autocomplete.sh
I was needing to answer some questions for a doctrine schema exporter so my file looked like this.
-- This is an example only --
php vendor/bin/mysql-workbench-schema-export mysqlworkbenchfile.mwb ./doctrine << EOF
`#Export to Doctrine Annotation Format` 1
`#Would you like to change the setup configuration before exporting` y
`#Log to console` y
`#Log file` testing.log
`#Filename [%entity%.%extension%]`
`#Indentation [4]`
`#Use tabs [no]`
`#Eol delimeter (win, unix) [win]`
`#Backup existing file [yes]`
`#Add generator info as comment [yes]`
`#Skip plural name checking [no]`
`#Use logged storage [no]`
`#Sort tables and views [yes]`
`#Export only table categorized []`
`#Enhance many to many detection [yes]`
`#Skip many to many tables [yes]`
`#Bundle namespace []`
`#Entity namespace []`
`#Repository namespace []`
`#Use automatic repository [yes]`
`#Skip column with relation [no]`
`#Related var name format [%name%%related%]`
`#Nullable attribute (auto, always) [auto]`
`#Generated value strategy (auto, identity, sequence, table, none) [auto]`
`#Default cascade (persist, remove, detach, merge, all, refresh, ) [no]`
`#Use annotation prefix [ORM\]`
`#Skip getter and setter [no]`
`#Generate entity serialization [yes]`
`#Generate extendable entity [no]` y
`#Quote identifier strategy (auto, always, none) [auto]`
`#Extends class []`
`#Property typehint [no]`
EOF
The thing I like about this strategy is you can comment what your answers are and using EOF a blank line is just that (the default answer). Turns out by the way this exporter tool has its own JSON counterpart for answering these questions, but I figured that out after I did this =).
to run the script simply be in the directory you want and run 'sh autocomplete.sh' in terminal.
In short by using << EOL & EOF in combination with Return Lines you can answer each question of the prompt as necessary. Each new line is a new answer.
My example just shows how this can be done with comments also using the ` character so you remember what each step is.
Note the other advantage of this method is you can answer with more then just Y or N ... in fact you can answer with blanks!
Hope this helps someone out.

Answer 6

There is a special build-in util for this - 'yes'.
To answer all questions with the same answer, you can run
yes [answer] |./your_script
Or you can put it inside your script have specific answer to each question