Unique File Names

[Angela]

I am using
$filename = "$$" . "$^T" . ".html";

to name my file for my Perl application. Will this always guarantee uniqueness of filename? If not how can I handle generally to name unique file names?

[sammy]

Yes this would ensure unique file name because in Perl the variable $$ denotes the process id that is used currently. In addition you have also used $^T which denotes current timestamp. So association of both these gives unique process id with current timestamp to filename making the filename as unique.

[Rahulbatra]

Sammy I agree that the variables denote current process id and the current timestamp making filename as unique. But there is a small thing here for consideration. The process ids are unique only up to a certain number. After it reaches the maximum number allowed there is possibility of the process id getting repeated again. Also attaching timestamp though makes it unique filename I feel it would give a bad shape to the filename.

[kiruthika_sri]

Use the function tempfile() which is in the module File::Temp.
Example

use File::Temp qw/ tempfile tempdir /;

$fh = tempfile();
my ($fh, $filename) = tempfile();
print "file:$filename";