Caching versus Extraction

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When your application requires write access to a file, Thinstall cannot write over the copy stored inside your EXE. Instead it will do one of 3 things.

1. Fail the write operation. If you have the option "Never cache / extract" enabled for this file write operations will fail.
Use this option when you want to ensure the file's contents will never be present on disk.

2. Extract the file to its full virtual path from the internal archive to the external file system. After the file has been extracted the application will receive a file handle to the real filesystem file. Option = "Extract on write/memmap"
Use this option if you know the virtual filename points to a location that can exists on the hard drive. If virtual path points to a drive letter that does not exist or points to a read-only location such as CDROM, this option will fail.

3. Extract the file contents to the designated "Cache Directory" using a unique filename on the real filesystem. After the file has been extracted the application will receive a file handle to the "cache file". Even though the cache file has a different path and filename on the real filesystem, it will appear to exist at its virtual path to the application. Option = "Cache on write/memmap"


Caching versus Extraction filenames

	Caching enabled	Extraction enabled
Real Files system data location	Cache_directory\file_hash (example c:\windows\temp\82947s9298sfh.ths)	Virtual path\Virtual Filename
Apparent file system data location (where data appears to be to your application)	Virtual path\Virtual Filename	Virtual path\Virtual Filename

Effect of Caching & Extraction on File Access