If you're talking about arrays as hash values, just use push. 
push @{ $Hash_filematches{ $filename } }, grep( /\/\Q$file_name\E#/i, 
+@{
+ $Hash_filenames{ $filename } });

[download]

That'll even work if $Hash_filematches{ $filename } doesn't exist yet, when this line is run, thanks to autovivification.

In reply to Re: How to append data in a hash by bart
in thread How to append data in a hash by iphone

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