Writing a persistent perl script

Question

I am trying to write a persistent/cached script. The code would look something like this:

...
Memoize(\'process_fille\');
print process_file($ARGV[0]);
...
s         


        

Answer 1

You can't get the script to keep state. As soon as the process exists any information not written to disk is gone.

There are a few ways you can accomplish this though:

• Write a daemon which listens on a network or unix socket. The daemon can populate my_hash and answer questions sent from a very simple my_script.pl. It'd only have to open a connection to the daemon, send the question and return an answer.

• Create an efficient look-up file format. If you need the information often it'll probably stay in the VFS cache anyway.

• Set up a shared memory region. The first time your scripts starts you save the information there, then re-use it later. That might be tricky from a Perl script though.