Example of Splitting a File Based on Value

#!/usr/bin/perl -w
use strict;
use diagnostics;

#- 1 --------------------------------------------------------------------------
print "\n";
print "+-----------------------------------------------------------------+ \n";
print "| splitdat.pl:                                                    | \n";
print "| Break a file into two output files based on values in an        | \n";
print "| operator-supplied column(s).                                    | \n";
print "|                                                                 | \n";
print "| The output will be written to the directory where the input     | \n";
print "| file resides.                                                   | \n";
print "|                                                                 | \n";
print "| Note: Type in the case (upper or lower) that the filename and   | \n";
print "| ----  value is in.                                              | \n";
print "+-----------------------------------------------------------------+ \n\n";

#------------------------------------------------------------------------------
print "Directory Name: ('.' = Current)\t";  # Ask for directory
my $Directory = <STDIN>;                    # Store what's typed in
chomp($Directory);                          # Get rid of line break

    chdir($Directory)                       # change to the directory
            or die "Invalid Directory \n";  #    or if invalid, die

#- 2 --------------------------------------------------------------------------
print "Input File:\t\t\t";                  # Ask for filename
my $InFile = <STDIN>;                       # Store what's typed in
chomp($InFile);                             # Get rid of line break

    open( INPUT,  $InFile)                  # Open the file if found.
            or die "The file $InFile could not be found.  \n";

#- 3a -------------------------------------------------------------------------
print "Primary Output File:\t\t";           # Ask for 1st output name
my $Out1File = <STDIN>;                     # Store what's typed in
chomp($Out1File);                           # Get rid of line break

    #- 3.1a -------------------------------------------------------------------
    open(OUTPUT1, ">$Out1File")             # Try to open 
            or die "The file $Out1File could not be opened for writing \n";

#- 3b -------------------------------------------------------------------------
print "Secondary Output File: \t\t";        # Ask for 2nd output name
my $Out2File = <STDIN>;                     # Store what's typed in
chomp($Out2File);                           # Get rid of line break

    #- 3.1b -------------------------------------------------------------------
    open(OUTPUT2, ">$Out2File \t")          # Try to open
            or die "The file $Out2File could not be opened for writing \n";

#- 4 --------------------------------------------------------------------------
print "Start Position to Search: \t";       # Get beginning of column
my $StartPosition = <STDIN>;                # Store what's typed in
chomp($StartPosition);                      # Get rid of line break
$StartPosition = $StartPosition -1;         # Starts from 0 so subtract 1

#- 5 --------------------------------------------------------------------------
print "Value to search for: \t\t";          # Get the value we're splitting on
my $SearchValue = <STDIN>;                  # Store what's typed in
chomp($SearchValue);                        # Get rid of line break
my $ValueLength = length($SearchValue);     # Get the length of the column

#- 6 --------------------------------------------------------------------------
my $InCount   = 0;                          # Initialize counters
my $Out1Count = 0;
my $Out2Count = 0;

#- 7 --------------------------------------------------------------------------
while(<INPUT>)                              # Read the input file
{ my $TheLine = $_;                         # Save the line's contents
  chomp($TheLine);                          # Get rid of the line break
  $InCount = $InCount + 1;                  # increment input count

  #----------------------------------------------------------------------------
  if (substr($TheLine ,$StartPosition       # Check the position for the value 
            ,$ValueLength)eq"$SearchValue") # requested. 
     { $Out1Count++;                        # Increment primary output counter
       print OUTPUT1 "$TheLine \n";         # write the line to the file
     } 
  else                                      # If another value, write to output2
     { $Out2Count++;                        # increment output count
       print OUTPUT2 "$TheLine \n";         # write the line to the file
     } 
}                                           # End of while(<INFILE>) loop
#------------------------------------------------------------------------------
print "\n";                                              # Print the
print "************************************* \n";        # results when done
print "* $0 COMPLETED SUCCESSFULLY           \n";
print "************************************* \n\n";
print "Record Counts: \n\n";
print "Input            -- $InFile:   \t  $InCount   \n";
print "Primary Output   -- $Out1File: \t  $Out1Count \n";
print "Secondary Output -- $Out2File: \t  $Out2Count \n\n";