Thank you Martin and everyone else.
On Oct 18, 2011, at 5:36 PM, Martin A. Brown wrote:
>
> You are asking perl to open a file called:
>
> /tmp/home/ubuntu/bin/test.count
>
> When, in fact, I guess that you would like to create the file:
>
> /tmp/test.count
>
Of course, you are correct. I didn't see it, but it made perfect sense when you
hit me with the clue sledge.
> A few notes and recommendations:
>
> 0. I would suggest renaming the script from 'test' to
> 'test-count-something'; there is a shell builtin called 'test'
> and often a binary /usr/bin/test, as well.
That's not the real name of the script. But noted.
> 1. To solve the fully qualified path issue from above, use 'basename'
> from the perl module File::Basename:
>
> use File::Basename;
> sub writetemp {
> my $fname = "/tmp/". basename($0) . ".count";
> open (NEWFILE, ">$fname") or die $!;
> print NEWFILE "$product{name}.value $product{value} $date";
> close (NEWFILE);
> }
Done, and it works as expected.
> 2. If you are going to write a file with one program and read the
> file with another program, get in the habit of creating the file
> atomically. Imagine what happens when your data file creation
> program is still writing a the data file when along comes the
> data consuming program and starts to read it! Hilarity.
>
> How do you do prevent this problem? Take advantage of
> filesystem atomicity. In perl, you can use the perl function
> rename:
>
> use File::Basename;
> sub writetemp {
> my $fname = "/tmp/". basename($0) . ".count";
> open (NEWFILE, ">${fname}.tmp") or die $!;
> print NEWFILE "$product{name}.value $product{value} $date";
> close (NEWFILE);
> rename($fname . ".tmp", $fname) or die $!;
> }
Excellent suggestion. I will implement this and the other suggestions. I'm a
novice when it comes to perl. I can usually cobble something together, but I
learn by example all the time.
> Wow, you are still reading.
Yes. I did read your whole message. :)
Thank you and everyone else for the help
Russell Johnson
[email protected]
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