awk - Why can't value of awk variables be passed to external functions ?


 
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# 8  
Old 11-22-2014
'exported functions' is a (questionable) bash-only feature.
system() runs /bin/sh so it only works if /bin/sh is bash.
--
Changing /bin/sh is a risk - e,g. system boot scripts might fail!
# 9  
Old 11-23-2014
Quote:
Originally Posted by MadeInGermany
'exported functions' is a (questionable) bash-only feature.
system() runs /bin/sh so it only works if /bin/sh is bash.
--
Changing /bin/sh is a risk - e,g. system boot scripts might fail!
So what should I do ?
# 10  
Old 11-23-2014
Quote:
Originally Posted by sreyan32
What you have told me to do doesn't work.
You messed up te same way in many places. Remember awk is not shell -- $k means column k. Stop using $k when you don't want column. Start using k.
# 11  
Old 11-23-2014
Quote:
Originally Posted by sreyan32
So what should I do ?
Ideally? You'd stop doing that.
# 12  
Old 11-24-2014
Using shell functions from within awk is difficult as you can see and it doesn't make too much sense. Write the same function in awk and use it in there!
# 13  
Old 11-25-2014
Quote:
Originally Posted by RudiC
Using shell functions from within awk is difficult as you can see and it doesn't make too much sense. Write the same function in awk and use it in there!
I am trying to get a concrete idea on what awk can and cannot do by pushing its less used and documented features to the limit.

Also, the symlink that you have provided in the beginning of the script using ln -sf. Is that permanent ? I mean will it persist even after script has ended ?
# 14  
Old 11-25-2014
Yes, that symlink is a permanent modification in the file system, nothing to do with the script. I only added it for demonstration purposes and told you to be careful and reset it after trying it.

BTW, you can't get back anything but the exit code from a system call inside awk.
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