Have you looked at what the documentation about chmod has to say? The examples show the various allowed usages of chmod. Note that chmod takes a string. Perl sees u+x as the numeric addition of the strings "u" and "x", and thankfully you are using strict so it prohibits using barewords as strings.

In reply to Re: How to use chmod u +x in perl by Corion
in thread How to use chmod u +x in perl by fearthechris29

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