Ouch! Look at the following: 

foreach $input(@inputarray) 
{
....

   @inputarray = (@newarraypreceding , @newarrayfollowing);
...

[download]
Never try to remove elements from the array you are currently looping through ... unless you are looking for trouble ;-) (or until you know exactly what you do!) This is probably the reason for your infinite loop.

Regarding speed: you do a lot of array-copying (splicing and putting together the arrays). Be aware that copying arrays is potentially slow ...

With your program you seem to want to create a list of filenames and check if they are existing in the filesystem. A typical approach would be to use a hash for the list of filenames (use the filename as keys!). For each filename you find in the file-system you would then check if a corresponding entry exists in the hash - and either mark it there or remove it.

If you really need the result in an array (which I doubt), you could create an array out of the hash once at the end.

HTH, Rata

btw.: looking up something in a hash is typically much faster than looking it up in an array...

In reply to Re: recursive loop and performace issue in find::file by Ratazong
in thread recursive loop and performace issue in find::file by Anonymous Monk

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