On Jan 17, 3:45 pm, [email protected] (David Christensen)
wrote:
> Ron Bergin wrote:
> > It's interesting that you found the warning message to be meaningless,
> > but the exact same message was helpful when you told the pragma to
> > raise the level of warnings to be fatal.
> > I should have said nearly the same message. Both messages told you where
> > the problem was located and with that info it should have been easy to
> > find/fix the problem. In my mind that's not meaningless.
>
> The root cause problem is that "perldoc -f print" does not describe what
> happens on error. I've filed a perlbug report to this effect.
>
Actually it does this... as you discovered in the doc:
Prints a string or a list of strings. Returns true if
successful...
In this case, $! is EBADF or "Bad file descriptor" which might
be due to some obscure OS error unknown to perl. So perl
can't necessarily pinpoint the exact cause with a meaningful
message at this stage but at least first warns you about the
unopened filehandle. (and that unopened filehandle warning,
as it turns out, is certainly a cause of EBADF).
And I'd agree that the docs should mention $! as perl does
here:
unlink Deletes a list of files. On success, it returns the
number of files it successfully deleted. On failure,
it returns false and sets $! (errno):
And many other perl i/o docs omit mention that $! gets
set and if there's failure such as truncate, stat, link, ...
However, $! may be generic and dying on an earlier warning
may not always be particularly meaningful in explaining what's
really happening as it did in your case.
--
Charles DeRykus
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