I'm a little confused. You said you are running on macosx, but your code starts with:

#!C:\Perl
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That makes no sense, and it entails that you can only run the script with a command line like this:

perl path/file_name_of_script arg1 ...
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(where the "path/" part is only needed if the script is not in your shell's current working directory). I would use this as the initial "shebang" line:

#!/usr/bin/perl
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because macosx is really a unix OS, and in unix, perl is typically found in the /usr/bin/ directory; macosx definitely has perl in that location. With that as the shebang line, and doing the shell command "chmod +x file_name_of_script", the script becomes available as a shell command:

path/file_name_of_script arg1 ...
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where the "path/" part is only needed if your shell PATH variable does not include the directory where the script is stored.

As for your question about iterating over a list of file names, a method that I find useful goes like this: the perl script expects as input a list of file names, loads those into an array, and then iterates over the array. At each iteration, if there's a problem with the file or its contents, issue a warning and skip on to the next file in the list; e.g.:

#!/usr/bin/perl

use strict;
use Getopt::Long;

my $Usage = "Usage: $0 [-p path] filename.list\n   or: ls [path] | $0 
+[-p path]\n";

my $path = '.';
die $Usage unless ( GetOptions( 'p=s' => \$path ) and -d $path );
die $Usage if (( @ARGV and !-f $ARGV[0] ) or ( @ARGV==0 and -t ));
    # need file name args or pipeline input

my @file_list = <>;  # read all input as a list of file names
chomp @file_list;   # get rid of line-feeds

for my $name ( @file_list ) {
    my $file = "$path/$name";
    if ( ! -f $file ) {
        warn "input value '$file' does not seem to be a data file; ski
+pped\n";
        next;
    }
    if ( ! open( I, "<", $file )) {
        warn "open failed for input file '$file'; skipped\n";
        next;
    }
    ...
}
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There are already very good shell command tools for creating a list of file names ("ls", "find"), and for filtering lists ("grep"), so I'm inclined not to rewrite those things in a perl script that is supposed to process a list of file names.

The exception to that rule is when the script is really intended for a specific task that always involves a specific location and/or filter for getting its list of file names to work on, because in that case, I'd rather not have to repeat the selection process on the command line every time I run the script.