appears to be entirely valid

Exactly! :)

Someone had forgotten a ZERO WIDTH NO-BREAK SPACE (which is encoded to ef bb bf in UTF-8) in the beginning of the file. Programmers' text editors usually highlight such "strange" characters, but in this case, my copy of Vim says that a three-byte file with this code point consists of "0 lines and 3 characters", but looks entirely empty.

In reply to Re^4: Need Help Porting XS Modules to Windows by Anonymous Monk
in thread Need Help Porting XS Modules to Windows by wbirkett

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