Put your list of files in @ARGV and then use <>.

#!/usr/bin/perl

use strict;
use warnings;

@ARGV = ('file2.txt', 'file4.txt', 'file15.txt');

open SEL, '>', 'selected.txt' or die $!;

while (<>) {
  print SEL;
}
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To expand on that, I do something which combines files specified by a glob into another. It is called like:

$ catfiles.pl *.txt *.html > mynewfile.txt
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And it looks like:

#!/usr/bin/perl
use strict; use warnings;
local $|=1; #turn of buffering

for ( map { glob $_ } @ARGV ) {
    open my $FH, '<', $_ or do {
        warn "Can't open '$_' for read, skipping: $!";
        next;
    }
    while (<$FH>) { print $_ }
    close $FH;
}
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Of course, on many systems cat *.txt *.html > mynewfile.txt works just fine, but this tool is useful because (a)I can extend it when I need to do more advanced work, and (b)Win32 doesn't have cat.

<-radiant.matrix->
A collection of thoughts and links from the minds of geeks
The Code that can be seen is not the true Code
"In any sufficiently large group of people, most are idiots" - Kaa's Law

Actually, Windows does have a cat equivalent, even though less powerfull. It is called type. Usage:

$type /?
Displays the contents of a text file or files.

TYPE [drive:][path]filename

$
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And of course you can redirect and/or append to files by using '>>' or '>' respectivelly.

too bad you never actually ran your code!

use strict;

my @files = qw(file1.txt file2.txt file3.txt);
my $merge = (@ARGV) ? shift : 'merged.txt';

open (BUFF, '>>', $merge) or die "Unable to open: '$merge'";

while (@files) {
    local $_ = shift @files;
    my $fileData = do { local (*ARGV, $/) = [$merge] and <> };
    print BUFF $fileData;
}

close (BUFF);
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sub catalanche
{
    system qq( cat "$_" >> "$_[1]" ) for @{$_[0]};
}

catalanche( \@sel_files => 'selected.txt' );
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Dear jdporter,
Is it possible to make your snippet above to print to STDOUT? I tried this modification in mycode.pl:

catalanche( \@sel_files );
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and then do this with mycode.pl:

$ perl mycode.pl > mydesired_outputfile.txt
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But it doesn't work. Hope to hear from you again.


---
neversaint and everlastingly indebted.......

Untested.

sub catalanche
{
    if ( @_ == 0 or $_[1] eq '-' ) # let - signify stdout as well
    {
        system qq( cat "$_" ) for @{$_[0]};
    }
    else
    {
        system qq( cat "$_" >> "$_[1]" ) for @{$_[0]};
    }
}
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We're building the house of the future together.

Doing cat with perl:

The first is simply a replacement for DOS or other systems which don't provide a cat command.

perl -p file1 file3 file14 file47 > selected.txt
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The second lets you list the files to be selected in a file. Instead of listing them all, one by one, you cat the file into the command list for the perl command.

perl -p `cat selection.list` > selected.txt
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If you are concatenating many files, being the restrictions of command line length, the third one uses a begin block to open the file, stuff all the names into @ARGV, replacing whatever was there before ( namely the name of the section file ), and lets the -p option output print all the files.

perl -p -e'BEGIN{ local $/; open LIST, '<', $ARGV[0]; my @list = <LIST
+>; @ARGV = @list; }' selection.list > selected.txt
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I your case the easiest way to do is: cat file*.txt >> finalfile.txt Greetings Naltagua

This post has more on *nix-like tools for Windows, including a link to source for cat.c from p. 154 of the Kernighan and Ritchie text. TMTOWTDI :-)

HTH,