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AWK break string into fields + pattern match

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# 1  
Old 10-13-2010
AWK break string into fields + pattern match
I am trying to break a string into separate fields and print the field that matches a pattern. I am using awk at the moment and have gotten this far:

Code:
awk '{for(i=1;i<=NF;++i)print "\t" $i}' longstring

This breaks the string into fields and prints each field on a separate line.
I want to add a pattern match to this using the posix version of awk, or replace the whole thing with sed or perl.
# 2  
Old 10-13-2010
Ok!

On each field, you can use AWK's "match" function, if it returns different from 0, it found the regex, so you can apply "sub" or "gsub" function on that field.

From AWK's man pages:
Code:
       match(s, r [, a])       Returns the position in s where the regular expression r occurs, or 0 if r is not present, and sets the values of RSTART and RLENGTH.  Note that
                               the argument order is the same as for the ~ operator: str ~ re.  If array a is provided, a is cleared and then elements 1 through n  are  filled
                               with  the  portions of s that match the corresponding parenthesized subexpression in r.  The 0āth element of a contains the portion of s matched
                               by the entire regular expression r.  Subscripts a[n, "start"], and a[n, "length"] provide the starting index in the string  and  length  respec-
                               tively, of each matching substring.

       gsub(r, s [, t])        For each substring matching the regular expression r in the string t, substitute the string s, and return the number of substitutions.  If t  is
                               not supplied, use $0.  An & in the replacement text is replaced with the text that was actually matched.  Use \& to get a literal &.  (This must
                               be typed as "\\&"; see GAWK: Effective AWK Programming for a fuller discussion of the rules for &ās and backslashes in the replacement  text  of
                               sub(), gsub(), and gensub().)

I hope it helps!

Regards.
# 3  
Old 10-14-2010
Thanks Felipe, the match function looks good.
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