Supplying arguments to a bash script that uses "read" rather than $#

Question

A bash script was provided to me by a sysadmin which requires three values to be input by me. The values are read using "read" rather than read directly from the command-line.

echo "Enter value:"
read myValue
echo "Enter value 2:"
read myOtherValue

The three values I'd be entering are predictable, and I need to run this script frequently, so I would like to automate it; however, simply executing the script with the params in the command-line does not work.

./script.sh myValue myOtherValue

I can supply the first value if I echo it and then pipe it to the script, but that only works for the first param. I don't know how to pass the rest of them in this fashion.

echo "myValue" | ./script.sh

I do not have access to modify the script to just read the arguments.

Any ideas?

score 5 · Answer 1 · answered Oct 23 '09 at 15:55

5

If the number of inputs is static you could use a here document:

cat <<FIN | ./script.sh
value1
value2
FIN

answered Oct 23 '09 at 15:55

Gerald Combs

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score 2 · Accepted Answer · answered Oct 23 '09 at 14:52

2

If you are truely unable to copy this script to your home folder and make modifications to suit your needs, you should look into expect. Expect can read/write stdin/stdout to a program in an automated fashion.

This guide looks decent: http://www.ftlinuxcourse.com/FTLinuxCourse_Complete-2004/FTLinuxCourse/en/sysadm/chap5_3.html

answered Oct 23 '09 at 14:52

Kyle Smith

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Leave it to me to try to over-engineer a solution when the path of least resistance is right in front of me. Thanks! – Michael Moussa Oct 23 '09 at 15:07
Are you referring to making a copy, or using expect? :) – Kyle Smith Oct 23 '09 at 15:12

score 2 · Answer 3 · answered Oct 23 '09 at 21:00

2

echo -e "MyValue\nMyOtherValue" | ./script.sh

answered Oct 23 '09 at 21:00

Bill Weiss

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Dennis Williamson · Answer 4 · 2009-10-23T19:14:27.303

1

Similar to Gerald Combs' answer, you can use process substitution and redirection:

./script.sh < <(echo -e "myValue\nmyOtherValue")

or

./script.sh < <(echo "myValue
myOtherValue")

or

./script.sh < <(cat <<EOF
myValue
myOtherValue
EOF
)

or even:

./script.sh < <(echo "myValue"; echo "myOtherValue")

Where, instead of two "echoes", you might have two different commands that produce the output you need for input to the script.

edited Oct 23 '09 at 19:14

answered Oct 23 '09 at 17:14

Dennis Williamson

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Shouldn't the last one read ./script.sh < <(echo "myValue"; echo "myOtherValue") ? – Kyle Smith Oct 23 '09 at 18:39

Supplying arguments to a bash script that uses "read" rather than $#

4 Answers4