I am writing a script to read a text file, say a.txt, which contains a list of text file to be analyzed, say b.txt, c.txt and d.txt. Each of the a, b and c will be opened and traced to capture a certain string using pattern matching. The result will be stored in corresponding log file. After that b.log will be treat as a reference, and c.log and d.log will be compared with b.log and the missing and extra entries of them will be output to result.list. This is the code I had written so far. 
#!/usr/bin/perl

print "Enter filename:";
chomp($fname = <STDIN>);

# Open the file which contains list of files to be opened.  If unsucce
+ssful, print an error message and quit.

open (file1,$fname) || die "Can't Open File: $fname\n";

while (<file1>)
{
  chomp;
  open (file2, $_);   # Open file in the list one by one
  $temp = $_;         # Store the file name to name the corresponding 
+log file
  print "$temp\n";    # Print the file name to indicate the different 
+output
  while (<file2>)
  {
    chomp;
    sub grep_pattern    # Print strings which contain the pattern
    {foreach ($_)
    {if (/$pattern/)
     {  print "$1\n";      
        open (file3, ">>$temp.log");    
        print file3 "$1\n";     # Print result in log file in append m
+ode
        close (file3);    
     }
    }
    }
    $pattern = 'hello '; # Find the pattern
    grep_pattern;
  }
  print "\n";   # Print a blank line to seperate the results from each
+ file
}
close (file1);

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But at best the log file should not be used and probably the intermediate result should be stored in some arrays or hashes and directly be compared. But I don't know how to create different array for each of the b.txt, c.txt and d.txt automatically. Anyone can help?

In reply to Compare multiple files and output differences by prescott2006

Title:
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