Open Source - Commercial Software?

Question

There's a lot of great open source code out there that comes in really handy for all sorts of common programming tasks. But upon reading carefully the licensing agreements, it seems to me that it's generally illegal to include such code in any standard commercial application.
Example:
A young programmer gets hired by a small software development company. The company gets a contract with a local business to write some custom applications for in-house use, and our programmer friend gets handed the specs. Several components of the software he is asked to write are already available as open source, and certainly more robust than anything he could write on his own.
Legally, he only has two options:
Convince his company and their client to release the final program as open source - even though it may have no use outside of their business and was never intended for public sale.
Write all the code himself, ignoring the open source resources, taking much longer to create an inferior product.
Does this make sense? Am I misunderstanding these license agreements? It would seem to me that, for instance, all those great and useful Apache products are perfect for commercial applications and indeed seem to be developed with that in mind. (I can't imagine using Log4J in a tiny program I hack out at home to organize my hard drive etc)
Note that there is a difference between open source software (MySQL, Apache web server, other such apps), and open source tools (Log4J, Apache commons, many more) in that the tools are not really useful on their own but instead are used as part of other programs. The licenses seem to allow free use of the software, but require open-sourcing of any derivative software - meaning that a company can use MySQL as a database for anything they wish, but a developer working for that company can't use Log4J to write a frontend for that database without releasing the frontend as open source???

Answer 1

But upon reading carefully the
licensing agreements, it seems to me that it's
generally illegal to include such code in anystandard
commercial application.I don't think so, although I'm no more a lawyer than
you are. The licence agreements vary widely. When I
look at the agreement for log4j, for example, I only
see the requirement that I have to put a copyright
notice and an acknowledgement in my software. No
prohibitions at all. That one's pretty
straightforward. But I'm still trying to make sense of
the LGPL.It all depends on the license.
Apache license allows ANY use and license for software using it as long as the Apache license is made available with a mention that components under that license have been used.
GPL on the other hand indeed requires that everything using any code released under GPL be released under GPL as well.
So if you were to write a 10MB application using a single 1KB GPLd module you have no choice but to release all your code under the GPL as well. This makes code under GPL impossible to use in commercial products or anything for which code needs to remain in-house for any reason.
Most other licenses fall somewhere in between. mySQL for example allows non-commercial use under any license but commercial use is barred unless you pay a license fee (in which case you get a different license).