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(g)awk how to preseve white spaces (FS characters) or read a right subpart of $0?


 
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# 15  
Old 07-29-2009
Quote:
Originally Posted by shri_nath
[...]
Could you suggest me a pattern that would also get rid of the very last (one or zero) characters from these: />*|@= ?

I tried
Code:
    gsub(/^([^ \t]+[ \t]+){6}[^ \t]+ (.+)[\/\>\*\|\@\=]{0,1}$/, "\\1", fileName);

but that did not work and so I am having the above left most seven fields removed first and then followed by another to gsub to remove the (zero or one) of those last charcters.
[...]
Well,
if that was "exactly one" or "one or more" and not "zero or one" with the GNU awk extension gensub you could write something like this:

Code:
gawk --re-interval 'NR > 2 && !/\/$/ {
  print gensub(/([^ \t]+[ \t]+){6}[^ \t]+ (.*)[/>*|@= ?]$/, "\\2", 1)
   }' infile

Notice that I'm using the re-interval option, because the gensub extension is disabled in compatibility (posix) mode and we still need the re-interval functionality.

In your case I would do it in two steps:

Code:
gawk --posix 'NR > 2 && !/\/$/ {
  sub(/([^ \t]+[ \t]+){6}[^ \t]+ /, "")
  sub(/[/>*|@= ?]$/, "")
  print
   }' infile


Last edited by radoulov; 07-29-2009 at 05:40 AM..

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