User Guide

10 Chapter 1: Reserved Words and Variables
You use the cflock tag to limit the scope of CFML constructs that modify shared data structures,
files, and CFXs, to ensure that modifications occur sequentially. For more information, see
cflock on page 270, and Chapter 15, “Using Persistent Data and Locking” in ColdFusion MX
Developer’s Guide.
Variable scope
ColdFusion supports the Variables scope. Unscoped variables created with the
cfset tag acquire
the Variables scope by default. For example, the variable created by the statement
<CFSET
linguist = Chomsky>
can be referenced as #Variables.linguist#
Caller scope
History
ColdFusion MX: The Caller scope is accessible as a structure. (In earlier releases, it was not.)
Client variables
The following client variables are reserved:
Client.CFID
Client.CFToken
Client.HitCount
Client.LastVisit
Client.TimeCreated
Client.URLToken
Server variables
Use the Server prefix to reference server variables, as follows:
Server.ColdFusion.ProductName
Server.ColdFusion.ProductVersion
Server.ColdFusion.ProductLevel
Server.ColdFusion.SerialNumber
Server.ColdFusion.SupportedLocales
Server.ColdFusion.AppServer
Server.ColdFusion.Expiration
Server.ColdFusion.RootDir
Server.OS.Name
Server.OS.AdditionalInformation
Server.OS.Version
Server.OS.BuildNumber
Application and session variables
To enable application and session variables, use the
cfapplication tag or Application.cfc.
Reference them as follows:
Application.myvariable
Session.myvariable
To ensure that modifications to shared data occur in the intended sequence, use the cflock tag.
For more information, see
cflock on page 270.