Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi , I have a DATA directory which contains files like this 
total 3
-rwxr-xr-x    1 me   unknown        26 Mar 12 09:53 Monday.db
-rwxr-xr-x    1 me   unknown        27 Mar 12 09:54 Tuesday.db
-rwxr-xr-x    1 me   unknown        26 Mar 12 09:54 Friday.db
-rwxr-xr-x    1 me   unknown        26 Mar 12 09:54 Dummy

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I am trying to open the directory and read each file and print the output of each file: 

 my $INFOFILES = "$HOME/DATA";

my @files=glob "$INFOFILES/*\.db";
print " the files are @files\n";
    for( my $idx=0; $idx < $#files + 1; $idx ++ ) {
        $file = $files[$idx];
        &process_file($file);
    }

sub process_file { }

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for some reason it is not storing any of the files under DATA inside the array @files. Any idea? thanks

Replies are listed 'Best First'.
Re: using glob to get files
by rir (Vicar) on Mar 12, 2004 at 16:32 UTC
    Perhaps you are shell-shocked.

    Do you mean/need: 

    my $INFOFILE = "$ENV{HOME}/DATA";

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    Be well.
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Re: using glob to get files
by pbeckingham (Parson) on Mar 12, 2004 at 16:41 UTC

    The following works: 

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

  foreach (glob "$ENV{HOME}/DATA/*.db")
  {
    process_file ($_);
  }

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    Please note that calling process_file() with that leading ampersand has side-effects that really surprised me when I first learnt of them.

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      If you are depending on the side-effects of not having the leading ampersand, you may be in for some surprises, too. Care to share more about your experiences with the evil ampersand?
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        To quote the good book (Camel, 2nd ed., p115) almost verbatim: 

        &foo(1,2,3);  # pass three arguments.
foo(1,2,3);   # the same.

foo();        # pass a null list.
&foo();       # the same.

&foo;         # foo() gets current args, like foo(@_) !!
foo;          # like foo() IFF sub foo pre-declared, else bareword "fo
+o".

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        The ampersand also disables any prototype checking on arguments not provided.

        Which means that under certain circumstances, using the ampersand can lead to unexpected results, so in my case, I tend to avoid it in all sub calls, so I don't have to remember the details.

        But I never called it evil, I just wanted folks to be aware that putting an ampersand in front of a sub call has odd behavior when no explicit arguments are passed. when I first read the Camel book, this section made me cringe.

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Re: using glob to get files
by Wonko the sane (Curate) on Mar 12, 2004 at 16:26 UTC
    Hello,

    This works fine for me. Are you sure your path is correct? Or that $HOME
    is populated with what you think it is?

    Wonko

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Re: using glob to get files
by borisz (Canon) on Mar 12, 2004 at 16:35 UTC
    try  my @files=<$INFOFILES/*.db>;
    Boris
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Re: using glob to get files
by Anonymous Monk on Mar 12, 2004 at 19:48 UTC
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