SAMS Teach Yourself Perl in 24 Hours THIRD EDITION

Hour 15. Finding Permanence

What You'll Learn in This Hour:

• Create a DBM file and store data in it

• Treat regular text files as a database

• Read and write to random positions in files

• Lock files for concurrent access

Writing Perl programs that find data in files or interact with the user is all well and good. But what happens when the program ends? The results are gone, you've got nothing to show for your effort, and you're left with this empty feeling—as though nothing had happened at all.

You may already be thinking of ways in which you could solve this problem in Perl based on what you have learned in previous hours, such as files, lists, and hashes. That would, of course, be the Hard Way.

Storing information for later retrieval the Easy Way is ...