Binary distributions for Unison can be found here.
The user manual can be found here.
Here's how to set up field validation based on dynamic values from another table.
Using the products.dbf table from the southwind sample database, validation can be added to the categoryid field to ensure it matches an existing categoryid from the categories.dbf table.
open database southwindThe rlookup() function checks whether an expression exists in the index (master or specified) of the specified table . An attempt to update categoryid with a value not in the list will give an error: Validation on field 'CATEGORYID' failed.
alter table products add constraint;
(categoryid set check rlookup(products.categoryid,categories))
If you have access to the Recital Workbench, you can use the modify structure worksurface to add and alter your dictionary entries, including a customized error message if required.

I am pleased to finally report that the Centos release of Redhats 5.3 has been built and is available for download from http://www.centos.org/
The highlights of this release can be found at the following URL: http://www.redhat.com
The main areas of interest in my opinion excluding critical secirty fixes are:
- Updated hardwaresupport support for the new Intel Core i7 (Nehalem) chips
- Beefed up virtualiseation support increasing CPU and Ram limits of Virtual machines.
- Inclusion of the fully open sourced OpenJDK. This makes Red Hat Enterprise Linux 5.3 the first enterprise-ready solution with a fully open source Java stack when combined with JBoss Enterprise Application Platform.
For those who already have Centos 5.2 installed you can simply receive the update via Yum.
Before you do the following, check that you do not have 3rd party repo's and the Centos-testing repo enabled.
You can display the currently enabled repo's using the following command.
$ yum repolist
Then as root at the prompt type:
$ yum update
System Requirements:
- Minimum memory: 4MB
- Minimum Diskspace: ~20MB
SE Linux is a feature of the Linux kernel that provides mandatory access control. This policy based access control system grants far greater control over the resources on a machine than standard Linux access controls such as permissions.
Many modern Linux distributions are shipping with SELinux enabled by default, Fedora 14 and Rhel 6 both install with it enabled.
When you run Recital Web on a SELinux enabled machine and navigate to the default.rsp page you will see something similar to the screen shot below.

If you launch the SELinux troubleshooter you will see the following problem.
SELinux is blocking the apache server from accessing the Recital server running on port 8001.

To manage you SELinux policy you must have the policycoreutils package group installed. The policycoreutils contains the policy core utilities that are required for basic operation of a SELinux system.
If you wish to use a GUI tool, you must install the policycoreutils-gui package.
At the command prompt execute the following:
As root
$ yum install policycoreutils
$ semanage port -a -t http_port_t -p tcp 8001
$ service recital restart
$ service httpd restart
We use the semanage command here to allow the http server access to port 8001. Once you have completed the steps detailed above you can go and navigate back to the default.rsp page in your borwser, where you will find the permission denied message is now replaced by the default.rsp page.

SELinux does a great job of restricting services and daemons so rather than simply disabling it, why not work with it!
When it comes to security, every little bit helps...
lslk lists information about locks held on files with local inodes on systems running linux.
Install it with:
yum install lslk
// declare an empty dynamic array
a = array()
// declare a simple dynamic array
a = array("barry", "recital", "boston")
foreach a as value
echo value
endfor
// declare an associative array
a = array("name" => "barry", "company" => "recital", "location" => "boston")
echo "length of a is " + len(a)
foreach a as key => value
echo "key=" + key + ", value=" + value
endfor