This variable defines a set of directories that the runtime searches to locate a data file. The default value is "." (current working directory). Data and code file search paths are described in more detail in Code and Data File Search Paths.

Directories can be a mix of relative and absolute paths. Entries are separated by one or more spaces. A space is a valid separator on all systems. Alternatively, on UNIX systems you can also separate entries with a colon. On Windows systems a semicolon can be used. On VMS systems a comma can be used.

You can specify a directory path that contains embedded spaces if you surround the path with quotation marks. For example:

FILE_PREFIX  C:\"Sales Data"  C:\"Customers"

Up to 4096 characters can be specified for the value of this variable.