FAQ 5.37 Why does Perl let me delete read-only files? Why does "-i" clobber protected fil...

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5.37: Why does Perl let me delete read-only files?  Why does "-i" clobber
protected files?  Isn't this a bug in Perl?

    This is elaborately and painstakingly described in the file-dir-perms
    article in the "Far More Than You Ever Wanted To Know" collection in
    http://www.cpan.org/misc/olddoc/FMTEYEWTK.tgz .

    The executive summary: learn how your filesystem works. The permissions
    on a file say what can happen to the data in that file. The permissions
    on a directory say what can happen to the list of files in that
    directory. If you delete a file, you're removing its name from the
    directory (so the operation depends on the permissions of the directory,
    not of the file). If you try to write to the file, the permissions of
    the file govern whether you're allowed to.


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