Unlink or rename?

iphone has asked for the wisdom of the Perl Monks concerning the following question:

I open a file to append some data but the next time when the script runs I want this file to be deleted so that the data doesnt get appended to the already existing file.I know there is an unlink command but I read somewhere that renaming would be a best option?I want to get the fellow monks opinion on this.Please let me know your suggestions

open(my $OUTPUT, '+>>', "my file.txt") or die $!;
if (@array)
{
print $OUTPUT "@array";
}
if (@array2)
{
pprint $OUTPUT "@array2";
}
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Comment on Unlink or rename? Download Code

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Re: Unlink or rename? by Anonymous Monk on Dec 22, 2010 at 06:38 UTC
I open a file to append ... doesnt get appended If you don't want the data appended, why open in append mode?	[reply]
Re: Unlink or rename? by samarzone (Pilgrim) on Dec 22, 2010 at 06:39 UTC
If you don't care for the old data why are you opening the file in append mode? Use '>' for opening file. You have also incorrectly written `my` where only file name should be. There is no value of a keyword inside double quotes if you are not `eval`ing it. It should be something like `open(my $OUTPUT, '>', "file.txt") or die $!;` Don't forget to close the handle `close($OUTPUT)` Update: As pointed by hossman and Anonymous Monk below, "my file.txt" has no problem as a file name. My assumption was that you were expecting a file named "file.txt" -- Regards - Samar	[reply] [d/l] [select]
Re^2: Unlink or rename? by Anonymous Monk on Dec 22, 2010 at 06:48 UTC
You have also incorrectly written my where only file name should be. `my filename.txt` is perfectly valid for a filename :)	[reply] [d/l]
Re^2: Unlink or rename? by hossman (Prior) on Dec 22, 2010 at 06:49 UTC
"my file.txt" is a perfectly valid filename on many filesystems.	[reply]
Re^3: Unlink or rename? by samarzone (Pilgrim) on Dec 22, 2010 at 07:00 UTC
Agreed. I believed the OP did not want the file name as "my file.txt" and instead he wrote `my` as a keyword. If it was as a filename then that's perfectly fine. Thanks for pointing :) -- Regards - Samar	[reply] [d/l]
Re: Unlink or rename? by MishaMoose (Scribe) on Dec 22, 2010 at 12:49 UTC
Leaving aside whether you should have opened the file in appned mode or not and to answer your question ... unlink or rename ... it depends 8^) if you want the file to be available for something after you have completed your processing then rename. If you really want to delete the file then unlink. As other have mentioned in some detail ... opening the file in write moide wil lclear any previous contents and unless you are opening and closing the file multiple times in the script appending doesn't really gain you anything Hope this helps! Misha/Michael - Russian student, grognard, bemused observer of humanity and self professed programmer with delusions of relevance	[reply]