in reply to Re: use lib and use autouse 'module'
in thread use lib and use autouse 'module'

Thanks for your quick response. I have information on the directory that this module will reside. The perl script is designed as a file watcher and the process files with the functions from the module. In the loop (for file watcher) i look to see if the common mount point exists and if it does then I call the modules function to process the file. so if I understand you correct, I could do 
## PERL SCRIPT ##

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

my $g_commonMount = "/common_mount";
my $g_moduleDir = "$g_commonMount/include";

sub fileWatcher
{
   while(1)
   {
      if ( -d $g_moduleDir )
      {
         use autouse 'foo' => qw/foo/;  #using your example
         unshift @INC, '$g_moduleDir';  #foo.pm is under $g_moduleDir
         foo;
      }

      sleep (10);

   }
}

#### MAIN ###
&fileWatcher;

__END__

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Re^3: use lib and use autouse 'module'
by Hue-Bond (Priest) on Jul 29, 2006 at 00:10 UTC

    Ah, the directory is known from the beginning. That makes things easier. There's no need to unshift anything, since you can use lib(*).

    #!/usr/bin/perl
## untested
use warnings;
use strict;

my ($g_commonMount, $g_moduleDir);
BEGIN {
  $g_commonMount = "/common_mount";
  $g_moduleDir = "$g_commonMount/include";
}
use lib $g_moduleDir;

sub file_watcher {
  while (1) {
    sleep 10, next unless -d $g_moduleDir;

    use autouse 'foo' => qw/foo/;
    foo;
  }
}

file_watcher;

    [download]

    I'm not particularly proud of the BEGIN block but maybe there's another way to do it. Also, instead of autouse(*), you can use require.

    (*) CPAN seems down now, so the links to the modules may be wrong, since they are core and I don't know if one can link to them in the same fashion as any other.

    --
    David Serrano

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[d/l]
      Thanks for your response. The directory name (only)is known at the beginning. The directory itself gets created (mounted) at a later time. So if this is the case, would the 
      use lib $g_moduleDir;

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      give a runtime error? When I tested this syntax in my perl script, It gave a message saying - Empty compile time value given to use lib. But then when I created the include directory, and called 
      require MY_MODULE;

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      it loaded the module and gave me access to all the functions and variables defined in the module. I noticed that this is not possible in autouse since we would have to specifiy all the functions and variables in the qw(). Appreciate your comments.
[reply]
[d/l]
[select]
        would the use lib $g_moduleDir;give a runtime error?

        Didn't yesterday when I posted that, and didn't right now. This is what I tried:

        use lib '/home/hue/nonexistent';
use autouse 'FOO' => qw/foo/;
sleep 10;
foo;

        [download]

        Then, in another console, did a mkdir nonexistent; mv FOO.pm nonexistent. No warnings or errors from the program, it just run seamlessly.

        Empty compile time value given to use lib

        It seems you passed an empty variable to lib. Check it.

        --
        David Serrano

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[d/l]

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