What does the "*" means when placed infront of a variable or reference?

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

I have been reading through some intermediate level code and I have come accross variables or references that have an asterix in front of them. I am trying to determine the significance of this asterix. Is it a pointer...???

Here are just a few examples of how I have seen them used:

  local(*dbline) = $main::{'_<' . $fname};
  local(*F);
  *GUI:: = \%Win32::GUI::;
[download]

I have tried to do searches on "*" but as you can imagine it is a hard thing to search on.

Thanks in advance to anyone that can clue me in on this.

update (broquaint): added <code> tags

Comment on What does the "*" means when placed infront of a variable or reference? Download Code

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Re: What does the "*" means when placed infront of a variable or reference? by edan (Curate) on Feb 18, 2004 at 14:55 UTC
That there is a 'typeglob'. Read the `perldoc perldata` page, specifically the section entitled 'Typeglobs and Filehandles'. Here's a link: http://www.perldoc.com/perl5.8.0/pod/perldata.html#Typeglobs-and-Filehandles -- edan (formerly known as 3dan)	[reply] [d/l]
Re: What does the "*" means when placed infront of a variable or reference? by broquaint (Abbot) on Feb 18, 2004 at 15:14 UTC
Used in that context, the `` is the sigil for globs (as `$` is the sigil for scalars and `@` the sigil for arrays and `%` the sigil for hashes). A glob is a 'storage unit' for package* variables, and globs themselves live within symbol tables (although they can also live seperate of them see. `Symbol`'s `gensym()`). For more info on globs see Of Symbol Tables and Globs. HTH `_________ broquaint`	[reply]
Re: What does the "*" means when placed infront of a variable or reference? by antirice (Priest) on Feb 18, 2004 at 14:54 UTC
They affect symbol table entries. For a better understanding of how they work, take a look at perldoc perlmod under the Symbol Tables section. antirice The first rule of Perl club is - use Perl The ith rule of Perl club is - follow rule i - 1 for i > 1	[reply]
Re: What does the "*" means when placed infront of a variable or reference? by ysth (Canon) on Feb 18, 2004 at 18:28 UTC
Translation of those lines: # %main:: is the main symbol table (the :: are part of # the variable name in this case) # lookup the entry for "_<$fname" (note that symbol # tables can contain not-normally-valid identifiers # that are accessible only via the symbol table hash or # via symbolic references) # in this scope only, alias dbline to {"_<$fname"}. # this will alias $dbline, @dbline, %dbline, etc. # though I'm guessing that only the filehandle is # actually wanted. local(dbline) = $main::{'_<' . $fname}; # for this scope, hide $F, @F, F, etc. and use fresh ones # typically used to say things like open F, ... without # worrying that some other code is using the F filehandle. local(F); # Make the GUI:: symbol table (aka package) an alias to # Win32::GUI:: GUI:: = \%Win32::GUI::; [download]	[reply] [d/l]
Re: What does the "*" means when placed infront of a variable or reference? by Anonymous Monk on Feb 18, 2004 at 16:23 UTC
Thank you all for the quick response, now that I have a starting point I can dig in....	[reply]