close or die

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Re: close or die by FoxtrotUniform (Prior) on Nov 11, 2004 at 22:42 UTC
Sorry for being pedant but we are opening files here, so - unless you mistype your file handle, - you can always close a filehandle. Or am I wrong? No need to apologize for being pedantic :-). I can't think of a situation where `close` would fail on a plain old file on a local filesystem; for that, it's just habit. But networked filesystems, sockets, pipes, and so on can mess up `close`; besides, Always Check System Call Return Values is a good habit to get into. `--` Yours in pedantry,`F o x t r o t U n i f o r m` "Anything you put in comments is not tested and easily goes out of date." -- tye	[reply] [d/l] [select]
Re^2: close or die by Fletch (Bishop) on Nov 12, 2004 at 00:50 UTC
According to `man 2 close` (FreeBSD, OpenBSD and OS X) the two cases are: `ERRORS Close() will fail if: [EBADF] D is not an active descriptor. [EINTR] An interrupt was received.` [download] </unecessarily complete information> But agreed, always checking the return value from system calls is good practice (just like you should always check your optics before testing your high powered laser when that jerk Kent's around . . . </Real Genius>). Update: Ooop, tilly is correct below. Perl's `close` is more akin to `fclose(3)` than `close(2)` and can return with `errno` of any of the errors from `close(2)` or `fflush(3)` (and `fflush(3)` in turn may set `errno` if an underlying `write(2)` failed).	[reply] [d/l] [select]
Re^3: close or die by tilly (Archbishop) on Nov 12, 2004 at 02:34 UTC
That's actually not complete information since Perl's close is more complicated than the corresponding C call. In particular when you close a file in Perl it also flushes data to the filehandle, which can fail if the filesystem is full. Would you like to get an error message when your file got truncated because the filesystem was full?	[reply]
Re^2: close or die by PerlingTheUK (Hermit) on Nov 11, 2004 at 23:09 UTC
Thanks, I sometimes need some help with my English. Besides I think the original request was rather lacking to understand that `my ( $a, $b, ... $z )` [download] is acutally an array. So it was my intention - and even though it was counter productive in the end - to avoid confucion of what is actually going on between open and close. BTW, my choice for reading a file into an array still is File::Slurp which was discussed quite exhaustively recently in a thread i just cannot find right now. Cheers, PerlingTheUK	[reply] [d/l]
Re^3: close or die by chb (Deacon) on Nov 12, 2004 at 08:39 UTC
Just to be super-super pedantic: `my ( $a, $b, ... $z )` is a list, not an array :-)	[reply] [d/l]