Storing output of an executable with multi-line input to a variable in shell script

Question

Kindly anyone help me out in doing this (as mentioned in the subject line). Tried various links on this website and on Google, but nothing is working. So, I want to store the output of C++ executable to a shell variable. Trying to do this like this:

printf '\n'
    printf '\n'
    printf '<h3>[Test case]</h3>'
    printf '<p>      Input: %s</p>' "$p"
    #out=`echo $p | ./Main << EOF `
    #out=`echo tamu 1 algo clrs 1234 5 1234 4 Q | ./Main`
    out = "$(echo ./Main <<EOF 
             tamu 
             1 
             algo 
             clrs 
             1234 
             5 
             1234 
             4 
             Q 
             EOF)"

printf '<p>      Your output: %s</p>' "$out".

But getting following error:

$ASNLIB/run_submission.sh: line 27: unexpected EOF while looking for matching `)'                                                                                           
    $ASNLIB/run_submission.sh: line 90: syntax error: unexpected end of file.

However, indentation and braces everything is correct. Also, just doing this:

./Main << EOF 
tamu 
1 
algo 
clrs 
1234 
5 
1234 
4 
Q 
EOF

gives me output but I want to store this output in a shell variable for further computation. Kindly anyone let me know how to do this.

So, here is the full file:

#!/bin/bash

trap cleanup 1 2 3 6 9

cleanup()
{
  echo "Critial error occurred. Program failed to run."
  exit 1
}

rm -f summary.txt

let "total_score=0"
passfail="PASSED"
let "Outcome=PASSED"

printf '\n'
printf '\n'
out =`./Main <<EOF 
         tamu 
         1 
         algo 
         clrs 
         1234 
         5 
         1234 
         4 
         Q 
         EOF`

echo "Your output: "
echo $out

printf '<p>====================================================================================================</p>'

printf '\n'
printf '\n'

ref =`./Main_ref <<EOF
         tamu 
         1 
         algo 
         clrs 
         1234 
         5 
         1234 
         4 
         Q 
         EOF`

echo "Expected output: "
echo $ref

printf '<p>====================================================================================================</p>'

python $ASNLIB/compare_string.py "$out" "$ref" > /dev/null

if [ "$?" != "0" ]; then
    printf '<p style="color:red;">[FAILED.]</p>'
    Outcome="FAILED"
    let "total_score=0"
    printf '<p><b>      Outcome: %s</b></p>' "Please follow all the instructions as mentioned in the lab-work. It seems that you have missed any of the following instructions. 1) Might you have not returned the value in Library.cpp file using reference. 2) Please be ensure that you also need to change the declaration of this Library::getBook() in Library.h file."
        printf '<p><b>      Total Score: %s</b></p>' $total_score
else
    printf '<p style="color:green;">[PASSED.]</p>'
    Outcome="PASSED"
    let "total_score=1"
    printf '<p><b>      Outcome: %s</b></p>' "Complete"
    printf '<p><b>      Total Score: %s</b></p>' $total_score
fi

echo "Correctness, $Outcome, $total_score, 1" >> summary.txt

I can see errors after doing changes as what is mentioned in the first comment which are as follows:

$ASNLIB/run_submission.sh: line 39: warning: here-document at line 29 delimited by end-of-file (wanted `EOF')                                                                                                 
    $ASNLIB/run_submission.sh: line 29: out: command not found                                                                                                                                                    
    $ASNLIB/run_submission.sh: line 59: warning: here-document at line 49 delimited by end-of-file (wanted `EOF')                                                                                                 
    $ASNLIB/run_submission.sh: line 49: ref: command not found

And the output of variables - "out" and "ref" is empty.

score 0 · Answer 1 · edited May 23 '17 at 12:00

0

What about

out=`./Main <<EOF
         tamu
         1
         algo
         clrs
         1234
         5
         1234
         4
         Q
         EOF`

EDIT

Remove the space before the equal sign:

out=`./Main <<EOF
# ...
ref=`./Main_ref <<EOF

Check this answer for more information about the use of spaces around the equal sign in Bash.

edited May 23 '17 at 12:00

Community

1
1

answered Mar 19 '17 at 20:35

cbuchart

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Thanks cbuchart...could you please further helped me out. Have modified the question above and posted the whole file. Thanks in advance! – Priya Arora Mar 19 '17 at 22:13
Updated, hope it helps you. – cbuchart Mar 19 '17 at 22:31
Glad to help! Please do not forget to accept the best answer so it will help everybody. – cbuchart Mar 19 '17 at 22:53

Storing output of an executable with multi-line input to a variable in shell script

1 Answers1