FAQ 5.38 Why does Perl let me delete read-only files? Why does "-i" clobber protected files? Isn't

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5.38: 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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