Searching Font Resource Directories when Adobe PDF Library Initializes

When your application starts, it will call the PDFLInitHFT() method to begin the initialization process for the Library.

When the Library initializes it compiles a list of all its available resources. In particular it identifies the file folders where the font and CMap files are stored on the local machine. The default locations include C:\Datalogics\APDFL18.0.5\Resources path on a Windows machine, but your font resources could be anywhere. The most reliable way to make sure that your application finds the files it needs is to define a dirList array, compiled before the initialization begins. This lists every folder that the Library should look for font files:

/* Populate the directory list */
pdfldata.fontDirList = {..\..\..\..\Resources\Font, ..\..\..\..\Resources\CMap}
pdflData.fontDirListLen = 2;
pdflData.cMapDirectory = ..\..\..\..\Resources\CMap.
pdflData.unicodeDirectory = ..\..\..\..\Resources\Unicode
pdflData.ColorProfileDirList = ..\..\..\..\Resources\Color\Profiles
pdflData.ColorProfileDirListLen = 1
pdflData.pluginDirList = ..\..\..\..\..\Binaries
pdflData.pluginDirListLen = 1

The directory list array does not list the font files themselves, just the names of the folders where the font files might be stored.

The Library is designed to make sure that this resource list stays up to date. Paths may be relative, as shown above, or fully-attributed. The dirList array should specify all locations that you want the application to find and search. This includes both your system default locations and any others you want to add.

When the Library examines a location for possible font resources, it looks at every file in that folder, one at a time, and compiles a list for its future use that indicates the files in that folder that are font resources and those that are not. The Library stores the results in a text file in that folder called “AdobeFnt*.lst,” such as AdobeFnt16.1.lst. The next time Adobe PDF Library is initialized, it will find this resource folder and look for the AdobeFnt*.lst file again.

If the Library can’t find AdobeFnt, it examines the folder contents again and compiles a new copy of this list file.
If other files have been added to the folder since the last time the AdobeFnt list file was created, the Library examines the folder contents again, and compiles a new copy.
If the Library finds the AdobeFnt list file and it is still the most recent file in that folder, the Library reads the records in that file again and moves to the next resource folder.
To make the Library initialization process as efficient as possible, then, make sure that your font resource folders do not hold any files that are not related to fonts.

If a user of your application complains of missing fonts in their documents or display, and insists that those fonts are actually on their system already, check your Library application to ensure that it is looking in the right areas to find those resources.

A good way to test to make sure that you have identified all of the local resource folders and included them in your dirList array would be to search the local machine for every copy of the AdobeFnt*.lst file you can find, and then delete them all. You will probably see many copies of this Adobe list file, as most Adobe Systems products create their own versions. You won’t cause a problem by deleting these files. The applications will simply generate new ones to replace them the next time they run. After you have deleted all of these files, run your application again, to initialize and then terminate the Library. Then, search the machine again to find the locations where an AdobeFnt*.lst file appears. This will tell you the directories that the Library is searching in to locate font resources. If you are missing one, add the folder name to the dirList array and then initialize the Library again.