DLI Implementation and Reference Guide - Datalogics

2.10 DLI Implementation and Reference Guide
this occurs, neither DLI nor the Adobe PDF Library should be used, and if possible,
the calling program should cease execution as soon as is feasible.
Concepts and Facilities: Guide to the DL Pager Composition System
Specifying an Alternate File System
The ASFileSys passed to dlpdfinit as its second argument will typically be either
NULL (specifying that the user has no preference for how DLI manages file input and
output) or the dlpdfmemfilesys call. Calling dlpdfmemfilesys will return the
ASFileSys record to the Datalogics memory file system for the Adobe PDF Library.
This file system keeps temporary files in memory, instead of on disk, resulting in
significantly improved processing speeds on some systems. You can create your own
ASFileSys and pass it in, if you wish more control over how files are manipulated.
NOTE: The included fonts must still be read from disk, and the PDF document
which is created will be written to a disk file, unless the steps described in
"Writing PDF Output to Memory" are taken. If the user has the means to specify
an alternative file system, that too may be passed into dlpdfinit.
Using a Graphics Cache
As of DLI v3.0.11, the DLI graphics cache has been enhanced to use the default
ASFileSys implementation provided to dlpdfinit for caching graphics. By
default, the graphics cache file size is limited to 1.5GB. Customers who wish to use
larger graphics cache files are advised to supply a filesystem to dlpdfinit which is
capable of reliably handling files of the larger size.
NOTE: The cache size limit is checked every time a document is destroyed; the
cache may therefore temporarily exceed the cache size limit. When setting the
cache size limit, please note that to resize the graphics cache, free space equal to
the sum of the cache limit and the "low water" mark is required. Files In Memory
users with large graphics workloads are advised to lower the cache size limit to a
number appropriate for their target environment.