November 11th, 1995: COMPONLY.DCU added and COMPRESS.PAS updated to provide for it (new source revision number 1:51).
COMPONLY.DCU is a version of the COMPRESS unit (TCompress component ) which does not require the BDE. As such, you can use it for all compression jobs *except* those requiring database operations (e.g. with TCBlobstream, TCDBIMage/TCDBMemo).
Thus, do NOT use COMPONLY if you are planning to use the components in COMPCTRL.DCU, but rather, use the original COMPRESS.DCU unit.
To use: COMPONLY can't be added to your library if COMPRESS is already there, as it defines the same (TCompress) component. Thus, remove COMPRESS.DCU from your library and add COMPONLY instead. Then go ahead and use the TCompress component as required.
September 12th, 1995: V1.5 released
=== Changes from V1.0: ===
1. LZH (patent-free) replaces LZW (patented by Unisys) as a built-in compression method.
2. TCompress-compatible LZW source and licensing information are supplied to registered users free of charge.
3. The change from built-in LZW to LZH support means that archives or database blobs compressed using TCompress V1.0 cannot be expanded successfully with the unregistered v1.5. GPFs or "invalid compression method" exceptions will occur.
Therefore, expand any important files from your archives BEFORE installing V1.5, and delete the old archives. Similarly, you should revert to a backup (non-compressed) version of the BIOLIFE.* database before running the V1.5 COMPDEMO.
4. A TCompressedFileHeader format change (see COMPRESS.HLP) now permits filenames/paths of up to 255 characters to be stored, and means that the file header size will vary according to the length of the stored filename (generally speaking, it will be shorter than in V1.0).
5. All uses of TFilename parameters (max 80 chars) have been dropped in favour of String (max 255 chars) to support the change in (4).
6. New protected methods GetFileHeader and PutFileHeader have been added to support the new filename handling.
7. In order to support LZH compression, a new parameter (Destsize) has been added to the DoExpand and OnExpand methods, and the parameter order of the former has altered.
8. An error in a routine which estimates free disk space before expansion has been corrected. In V1.0, it occasionally led to spurious I/O errors when expanding a file from an archive. Also, stream write errors (such as a full disk) during compression now leave the archive in a "safe" state and generate an EInsufficientDiskSpace exception.
9. Additional (local) registration options now exist. See the Registration section of COMPRESS.HLP or README.TXT for more information.
10. All help files, example programs and documentation have been updated to reflect the above changes from V1.0 to V1.5, and minor documentation corrections have been made.
