currently, on projects where users get to input information, i ID that information using the following code: 
my $id = "$^T$$";
print $id;

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$^T is the basetime (measure of seconds since 1970)
$$ is the current process ID

I implemented this method thinking it's the most reasonable method instead of tracking and incrementing a number. Here's my question, is this a foolproof method of ID'ing user input? My concern doesn't deal with $^T (because obviously time only moves forward), but instead with $$ which i'm thinking can be reset at one point or another.

In reply to method of ID'ing by Parham

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