Top Forums Shell Programming and Scripting Displaying the first field if the second field matches the pattern using Perl Post 302727119 by royalibrahim on Monday 5th of November 2012 09:11:18 PM
Quote:
Originally Posted by elixir_sinari
The code you've provided does what it's supposed to do.

First of all, you are opening the file myfile, reading it completely and then closing the associated filehandle, once for each line in the file dummy_file.

For every line from dummy_file in which the 2nd field $F[1] (split on white-space using the -a run-time switch) matches the pattern patt anchored at the end, the first element of the list slice (split(" ", $i))[0], obtained by splitting the line from myfile on white-space, is displayed.

What exactly are you trying to do? Please elaborate with input and output samples.
Thank you, but the dummy file is just an empty file to fulfill or complete the syntax (else Perl reads from stdin). The actual file in action is "myfile" where I am looping over its contents by reading from the file handle 'F'. The white space splitting is done on the myfile's contents and not of the dummy file.

Lets say, my input is, myfile's contents:

aa bb cc
1a 2a 3a

I would like to get the output as:
aa

where 'bb' is the pattern to be matched.
 

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