0
115:wc -l:find . -iname "*test*":find /tmp/ -iname "*test*"

I would like to parse the string above.

In my case, a string consists of 4 columns (every command has : separator) but it can be much longer. I want to "pull out" all the commands including initial number, starting with 115 and continuing with wc -l, -iname "*test*", find /tmp/ -iname "*test*" ... always without : separator.

My variable $var should get those values:

var= 115 , var= wc-l , var= find . -iname "*test*" , var= find /tmp/ -iname "*test*"

My code:

while read line;
 do
 while [[ $var -ne '0' ]];
   do
    var=$( echo $line | cut -d ':' -f$i )
    i=$( expr $i + 1 )
    echo $var
   done
done <$1

I read lines from file and with second while I cut columns until empty one. Obviously, there is something wrong because echo do not print anything.

4
  • 1
    Sounds a bit like you want us to do your homework. Can you elaborate on what you tried already?
    – Minix
    Commented May 19, 2015 at 20:56
  • Pardon me! I tried to cut column by column but result is just not satisfying. var=$( echo $line | cut -d ':' -f1-4 | tr ':' '\n' )
    – ZeroZek
    Commented May 19, 2015 at 21:46
  • please elaborate on how your result was not satisfying and use the edit functionality to add it to the question. It will be easier to help you that way :)
    – Minix
    Commented May 19, 2015 at 21:56
  • 1
    I added some code :). Hope now is better to understand. Thank you!
    – ZeroZek
    Commented May 20, 2015 at 9:26

1 Answer 1

1

Here is your script fixed to work the way I think you meant it to work:

i=1     
while read line;                        
  do     
  while :; do 
    var=$( echo $line | cut -d ':' -f$i )                                   
    i=$( expr $i + 1 ) 
    [[ "$var" != "" ]] || break
    echo $var
  done     
done <$1

A couple of remarks:

  • i was not initialized
  • var was not initialized either, so the inner loop would not execute even once
  • I'm not sure what [[ $var -ne '0' ]] tests, but I think comparing $var to an empty string is better.
  • As a consequence, if there is an enpty field (i.e. two consecutive colons), this script will terminate there

A more robust way of doing the same thing is:

while read line; do
  num_fields=$(echo $line|awk -F':' '{print NF}')
  for (( i=1; i <= num_fields; i++ )); do
    var=$( echo $line | cut -d ':' -f$i )
    echo $var
  done
done <$1
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