Shell Programming and Scripting

Hello!
I need help I have a file like this:

Code:

AA BC FG

RF TT GH

DD FF HH

(a few number of rows and three columns) and I want to put the letters of each column in a variable step by step in order to give them as input in another script. So I would like to obtain:

for the 1° loop: var1 = AA var2 = BC var3 = FG

for the 2° loop: var1 = RF var2 = TT var3 = GH

for the 3° loop: var1 = DD var2 = FF var3 = HH

Thank you in advance. Best regards

Welcome edekP,

I have a few to questions pose in response first:-Most importantly, What have you tried so far?

There are probably many ways to achieve most tasks, so giving us an idea of your style and thoughts will help us guide you to an answer most suitable to you so you can adjust it to suit your needs in future.


We're all here to learn and getting the relevant information will help us all.

Kind regards,
Robin

Dear Robin,
thank you for your reply!
No, it isn't a homework, I am starting to use bash script so I have some problem
I know that I can print a value of a column with awk + print option, but I don't know how to select the row and how to "put" the values in a variables.
I think that maybe the best way for doing it is to use a "for" loop and with awk print the column $1 $2 $3.

Thank you in advance for your help.
Best.

Can you try the below one ?

Code:

 while read var1 var2 var3 ; do echo var1:$var1 var2:$var2 var3:$var3; done < file

Yes, It works! Could you explain me how work "while read"?
How does it understand to put the values in the variables?
I know that maybe it is a stupid question but I have never used that command.
Thank you in advance!

Hi,

Hope this helps.

Sorry, I have another question...
if the file has different number of column how can I do it?
I saw that with while read line it is possible to read all line, but how can I define a number of variable that change with the number of column?
For example if the file is:

Code:

AA FG TH
AD FR HK LO
AX DF ER TR
AZ SD WE

Thank you in advance.

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