This week, I continue the coverage of validation lists and validation list entries, which I began in the June 11 issue of this newsletter. In that article, I discussed the basics of validation lists and the anatomy of validation list entries, and I also provided new validation list commands. I recommend reading the article, if you haven't already. A link is provided at the end of this article.

As I've demonstrated in my earlier contributions to this column, you'll often build the validation list APIs and functions directly into your applications. You can also find links to these articles at the end of this article. However, while developing and testing these applications, you'll often need to create, change, verify, and remove validation list entries to make sure that everything works the way you've designed and planned. This is where the Add Validation List Entry (ADDVLDLE), Verify Validation List Entry (VFYVLDLE), Change Validation List Entry (CHGVLDLE), and Remove Validation List Entry (RMVVLDLE) commands I present today can offer some assistance.

*Read more about validation lists and the ADDVLDLE, VFYVLDLE, CHGVLDLE, and RMVVLDLE CL commands.

I was sitting here struggling to find a new and exciting topic for this week's newsletter when I received an email from a colleague who wanted to write log entries from RPG to a Syslog server. He said it was hard to find information and wanted to know if I had worked with it.

As luck would have it, I have in fact worked with Syslog. I had not previously thought of using it as a way of logging messages from an RPG program, but why not?

Syslog is the logging tool originally used in Unix environments. In addition to ordinary computers, many of today's network appliances also support Syslog, and that has made Syslog ubiquitous. Better yet, Syslog can send its log entries in realtime over a network to another server. This lets you consolidate your logs because all your applications and network appliances can write their logs to a common server. Instead of having to log on and check the logs of dozens (or even hundreds) of individual machines, you can check them all together in one place.

It makes perfect sense to me that RPG business applications might want to write log entries to Syslog as well--so this article shows you how.

I really like the db2 command available in QShell. It's a simple shell command that runs an SQL statement it receives as a parameter. It will even return result sets from SQL SELECT or CALL statements. Not only is this tool useful from QShell, but it's also useful in CL programs, because CL doesn't have its own embedded SQL like other ILE languages do.

Unfortunately, the db2 command from QShell is missing some details--small things that seriously reduce its value as a programming tool. If it fails, it doesn't report the failure via its exit status like other QShell utilities do, and that makes error handling very difficult. It also doesn't support the system naming convention that's widely used in native applications, which means you can't use the library list. It always outputs column heading information whether you want it or not. These limitations drove me crazy, so I wrote my own utility as a replacement. My utility is intended to work exactly like the QShell tool, except that it solves these problems and adds a few new features.