As of this FAQ's most recent release date, Informix-SE has been formally tested on the following platforms (all Intel):
The release notes for the glibc version state that this version was tested on a Pentium II 400 Mhz box running RedHat 5.1. Similary, the release notes for the libc5 version state that the libc5 version was tested on a Pentium II 400 Mhz box running OpenLinux 1.2.
Informix has two separate ports now. The original version was compiled with libc5 and ran unmodified on distributions such as Caldera's OpenLinux 1.2, S.u.S.E. 5.2, Slackware 3.5 and older and Debian 1.3. Informix promised from the outset to support the new glibc (a/k/a libc6) so that RedHat users would also be able to use it. Informix delivered on that promise during the final week of October.
Those using glibc/libc6-based systems may be able to run the libc5 version if they also install libc5 runtimes. This is an unsupported configuration, so if you futz your system, don't blame me. Several people report running such systems without incident, but, caveat emptor. Instructions for installing libc5 on glibc/libc6 systems exist; see Additional Resources at the end of this document.
NOTE: If you live outside the United States, you should call 800-331-1763. I have heard that dialing 800 numbers from outside the United States is not always possible, however, so you may want to contact the closest Informix office. For a list of locations, visit http://www.informix.com/informix/contact/offices.
Before you can download Informix-SE, you have to register at the Intraware site, since they are handling the downloads for Informix. Registration is free, and the questions asked are not too intrusive. To register, go to http://www.intraware.com/idn/linux/index.html and follow the prompts. You will receive a usercode and password via email from Intraware within a few hours (I received mine about twenty minutes later). Print this information out and make backup copies.
To order the CD, call 800-331-1763.
After receiving your Intraware usercode and password, surf on over to http://www.intraware.com/idn/linux/index.html and click on the "Download Page" link. Make the selections that fit your system. Unless you know you need the language supplements, only download Informix Connect Version 7.24.UC5 and Informix SE Version 7.24.UC5.
You wind up with a 9.5 Mb zipped file named
informix_se___esql_c_bundle_for_linux.zip.
You wind up with a 12.1Mb zipped file named (I kid you not!)
informix_se___esql_c_bundle_7_24_uc5_for_linux_on_kernel_2_0_34__glibc_2_0_7__red_hat_.zip.
This is a strictly optional step, although highly recommended. IDN is the Informix Developers Network. Through the registered areas of IDN you obtain access to the Linux users' forum hosted by Informix, technical notes and other information.
Again, this is an optional step, although, again, I strongly recommend it. IIUG is the International Informix Users Group. It is mostly the IIUG that we have to thank for persuading Informix to start porting their products to Linux. For Linux users, highlights of the IIUG site include several HOWTOs for getting Informix-SE up and running on your machine, a complete, searchable archive of comp.databases.informix and a grundle of code that will help you use your new installation of Informix-SE and make the job of maintaining it easier.
The development bundles is free and does not expire, so you can install it and use it to your heart's content. Which is to say, "There is no catch."
However, and although I wouldn't necessarily consider it a "catch," if you develop an application on top of Informix-SE and distribute it, you will have to buy a runtime-license for each user of the engine. You can also purchase support contracts for development needs. Informix is not in this for free and expects to see some payoff for their efforts.
For more information, contact an Informix sales office: http://www.informix.com/cgi-bin/contact.pl
Yes, but TANSTAAFL. Support contracts will cost you money. Why? Those familiar with the RDBMS business understand that support contracts constitute one of the three major revenue sources for RDBMS vendors (the other two sources are run-time licenses and consulting fees). This may surprise new kids in the sand box who are accustomed to the "free" "technical support" from other software vendors. Worth noting, however, is that support contracts generally buy you much better service and support than the free technical support offered by, for example, Microsoft or Dell.
For more information about technical support contracts: http://www.informix.com/informix/services/csp
That said, several Informix employees and many long-time users of Informix products hang out in comp.databases.informix. My own experience has been that c.d.i. and its companion mailing list are a fast source of support. c.d.i.'s inmates are patient and fairly tolerant, but I STRONGLY recommend that you do your homework before posting - search DejaNews ( http://www.dejanews.com) and lurk in the group before posting. Since "there is nothing new under the sun in c.d.i." (with apologies to Ecclesiastes) you will also want to read the Informix FAQ [ http://www.iiug.org/techinfo/faq/faq_top.html ] maintained by David Williams and hosted at the IIUG site.