Why I decided to develop FLoM

Before or later every Linux (and UNIX) system administrator must implement some form of synchronization between two or more commands/scripts. Typical synchronization scenarios are:

• it’s necessary to preserve system resources (too much commands of the same type should not be executed at the same time)
• it’s necessary to preserve data integrity (a file should not read until the writer completed)
• it’s necessary to guarantee process consistency (a command must be executed after the completion of another command)

Sometimes the problem is trivial and synchronization can be obtained simply by command concatenation… Sometimes it’s not as easy as that and a system administrator has to synchronize commands/scripts executed by independent scripts. UNIX exists by a lot of time, uhm, a huge amount of time, and a lot of solutions have been implemented.

Take a look to Google results: query string shell script lock

Google told me he knows about 16.900.000 “solutions” of this problem… bingo!

But are them really solutions?! Unfortunately not: most of the times, they are great hacks that solve a specific problem, not a class of problems.

At that point I asked myself:

If

nice command

allows me to run command with a specific priority, why can’t I use

flom command

to run command with a specific synchronization?

Trying to answer the above question, I started to develop FLoM, the Free Lock Manager!

Along the path I tried to address the above issue while keeping everything as easy as possible to use!