HTML version of the WHD Archive Extractor documentation.
Command-line extraction tool for WHDLoad archives on AmigaOS
WHD Archive Extractor is a command line tool for the Amiga that scans a folder tree for WHDLoad archives (.LHA and .LZX) and extracts them using Amiga-native archive tools.
It was written mainly to help process larger WHDLoad archive collections directly on the Amiga. Extracting these archives on other platforms can sometimes cause problems with Amiga file attributes or file names, so this tool keeps the whole process on the Amiga using the usual archive tools.
The program can scan through subdirectories, preserve the original folder layout, and process large numbers of LHA and LZX archives in one run.
C: (required; the program will not run without it)C: (optional; needed only for LZX archives)The program detects which LZX tool version is present and adjusts its command syntax accordingly. Both UnLZX 2.16 and LZX 1.21 are supported.
There are two ways to run the program:
WHDArchiveExtractor <source> <destination> [options]
WHDArchiveExtractor <source> -testarchivesonly [options]
The first form extracts archives found under the source folder into the destination folder, preserving subfolder structure. The second form tests archives without extracting them.
Options can appear in any order after the positional arguments.
Example: Extract all archives from a WHDLoad collection
WHDArchiveExtractor DH1:WHDLoad/Games DH2:Games
Example: Test archives without extracting
WHDArchiveExtractor DH1:WHDLoad/Games -testarchivesonly
Example: Extract, skipping archives already extracted, with summary
WHDArchiveExtractor DH1:WHDLoad/Games DH2:Games -skipifdestexists -writesummary
Enables a free disk space check before the run starts and before each archive is extracted. The minimum threshold is 20 MB. This option is off by default because the check adds overhead. It only applies in extraction mode.
Tests all archives found in the source tree without extracting them. No destination folder is required. The program uses each archive tool's built-in test command to verify integrity.
Note: UnLZX 2.16 does not support archive testing, so LZX archives are skipped when that version is detected. LZX 1.21 supports testing normally.
When all tests pass, the summary prints:
Archive test result: no damaged archives found.
Any test failures are logged to a timestamped file:
test_errors-YYYYMMDD-HHMMSS.txt
In extraction mode, skips any archive whose resolved destination drawer already exists. This is useful for repeat runs over the same source folder to avoid re-extracting archives that were already processed.
The check is based on whether the destination drawer exists, not on comparing archive contents.
Successfully extracted archives are logged to a timestamped file:
New-YYYYMMDD-HHMMSS.txt
Suppresses per-archive skip messages when used with -skipifdestexists. Instead of printing a line for every skipped archive, the program prints a progress heartbeat every 250 entries so you can see it is still working.
Applies drawer icons to newly created destination drawers during extraction. The program looks for a matching icon file in PROGDIR:Icons/<drawer_name>.info.
If no matching icon is found, a default Workbench drawer icon is used instead. Existing .info files are never overwritten. Icon failures are non-fatal and counted in the summary.
Writes a timestamped debug log file to the program directory:
error-YYYYMMDD-HHMMSS.txt
This log captures additional context for failures, fallback events, and other diagnostic details not shown on the console.
Controls the amount of console output:
NIL:. Prints one progress line per archive during extraction. Warnings and errors are still shown.Writes a machine-readable summary of the run to a fixed-name file:
PROGDIR:WHDArchiveExtractor_last_run.txt
This file is overwritten on each run. It contains key=value pairs including source and destination paths, archive counts, extraction results, elapsed time, and overall status.
The program checks for required tools at startup. LHA must be present in C: or the program exits immediately. UnLZX or LZX in C: is optional; if missing, LZX archives are detected but skipped.
The source folder is scanned recursively. Every .LHA and .LZX file found is queued for processing. File extension matching is case-insensitive.
For each archive, the program resolves the destination drawer path by combining the output directory with the relative subfolder structure from the source tree.
For LHA archives, the program inspects the archive listing to determine the top-level drawer name inside the archive and uses that as the destination drawer name. For LZX archives, or when no top-level drawer is found, the archive filename (without extension) is used.
Before extraction, the program checks for conflicts:
In extraction mode, the program creates the destination drawer path first, then runs the appropriate archive tool command. If destination drawer creation fails, the program falls back to letting the archive tool create the folder itself.
For LHA archives that overwrite an existing destination, the program clears protection bits on existing files before extraction to avoid overwrite failures.
The program stops scanning if 40 extraction errors are reached in a single run.
At the end of the run, a summary is printed showing totals for archives found, extracted, skipped, and failed, along with elapsed time and any error details.
The program can create several log files depending on the options used:
-debug is active.-skipifdestexists is active in extraction mode.-testarchivesonly is active and test failures occur.-writesummary is active. Located in PROGDIR: and overwritten each run.For other related Amiga utilities, including WHDFetch, which can download, filter, and extract Retroplay WHDLoad archives directly on the Amiga, visit madeforworkbench.com.