String match and do the condition

Question

When I try to match a string and do some conditions; it always fails to do so.

date=`date +%Y%m%d`
kol="/home/user/test_$date"
regex='Terminating the script'

if [ -f $kol ]; then

  sudo tail -f $kol | while read line; do 
     if [[  $line  = *"Terminating the"* ]]
     then

        echo "failed"

     else

        echo $line >> /home/user/test123_$date

     fi
else

   echo "File is not yet present"
   exit 0
fi

I have also tried with regex and that to failed. So when ever I input the matching string into the file ($path) it wont output "failed"; Is there anything wrong in the code. Help is much appreciated.

try putting then after ";" of if condition instead of next line and also add "" around $line , it should work fine — pritesh agrawal, Jul 04 '17 at 03:32
What does "fails to do so" actually mean? Do you get an error message? Can you provide sample input that can be tested with your script? Note that `$path` is a reserved variable name. Consider testing your scripts at [shellcheck.net](http://www.shellcheck.net/) before posting, as well as doing your own syntax check with `bash -n yourscript.sh` — ghoti, Jul 04 '17 at 03:39
@ghoti I didn't get any error messages but never the expected output too; there are no errors in syntax. — Sajeesh Krishnan, Jul 04 '17 at 04:20
@SajeeshKrishnan , what is the content of your file , can you please share , the lines which matches the condition. — pritesh agrawal, Jul 04 '17 at 04:26
Try adding `set -x` at the top of the script, and it'll print what it's doing as it runs. Add the output from when it tests the line that contains "Terminating the" to your question; it should clarify what's happening as the script runs. — Gordon Davisson, Jul 04 '17 at 07:22
`path` is not reserved; `PATH` is (or rather, it already has a special meaning and should not be used for your own purposes). — chepner, Jul 05 '17 at 13:54

Nurjan · Answer 1 · 2017-07-04T04:28:12.427

0

You can try this. At least it works for me:

sudo tail -f $1 | while read line; do

    if [[ $line = '' ]] 
    then
        break
    fi

    if [[  $line = *"Terminating the"* ]]
    then
        echo "failed"
    else
        echo $line >> /home/nurzhan/test123_$date
    fi
    done < "$1"

$path is parameter to the running script. Also note that by default the command tail returns only 10 last lines.

edited Jul 04 '17 at 04:28

answered Jul 04 '17 at 03:51

Nurjan

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it didnt work; it always echo's "failed" when i run with the changes. – Sajeesh Krishnan Jul 04 '17 at 04:21
@SajeeshKrishnan What doe you input file contain? I checked the script it works for me fine. – Nurjan Jul 04 '17 at 04:23
Its a log file created for the date and when then log fails logs "Terminating the" it should match the regex and output the echo if not write the $line to the other file. Thanks! – Sajeesh Krishnan Jul 04 '17 at 04:29
@SajeeshKrishnan Let's clarify, if the line contains "Terminating the" then it should go to the file test123_$date? Or it is the other way round? – Nurjan Jul 04 '17 at 04:32
it's the other way around; if the $line contains "Terminating the" it should echo "failed". – Sajeesh Krishnan Jul 04 '17 at 04:34
@SajeeshKrishnan, I checked my script on a simple input file and it worked as expected. Check yours more thoroughly. – Nurjan Jul 04 '17 at 04:36

String match and do the condition

1 Answers1