It does something analogous to the type of wild-card expansion that *nix shells do:

@ARGV = '*.pl';;

@ARGV = map{glob} @ARGV;;

print for @ARGV;;
1.pl
100GB.pl
1gbdb.pl
24to32.pl
...
[download]

C:\perl\bin>perl script.pl N:/TEMP/*
[download]

Use of uninitialized value in numeric lt (<) at script.pl
line 8.
        N:/TMP/*
[download]

I agree that

 @ARGV = map{glob} @ARGV;
....
[download]

does work, however, I think since "glob" can do the expansion, why not use

my @smaller_than_1000 = grep { -s $_ < 1000 } glob("@ARGV");
....
[download]

see glob for detail.
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me

That works for this application, but wouldn't for the more common uses:

BEGIN{ @ARGV = map glob, @ARGV }
while( <> ) {
   ...
}
[download]

And

perl -eBEGIN{@ARGV=map{glob}@ARGV} -nle"1" a*.pl b*.pl
[download]

---

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

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