411 is a nice help utility which works with MPW (Macintosh Programmers Workshop).
If you own MPW, the following paragraph tells you how to integrate the OpenDoc™ help files with the existing MPW 411 help files.
How to install the OpenDoc™ 411 Files
1. If you have not installed 411 in to your MPW setup, then install 411 from ETO or another source.
2. Copy the files "OpenDocHelp" and "OpenDocHelp.index" into the same folder as the rest of your 411 …Help files.
3. Choose "Edit 411 Files…" from the 411 menu inside MPW
4. Copy & paste the first line, and change the first line to end with "OpenDocHelp"
here is a sample Help_Files file:
HD80:411:CIncludesHelp
HD80:411:CommToolBoxHelp
HD80:411:InsideMacintoshHelp
HD80:411:MPWHelp
HD80:411:PInterfacesHelp
HD80:411:ResourcesHelp
HD80:411:TechNotesHelp
here is the same file after the change in step 4.:
HD80:411:OpenDocHelp
HD80:411:CIncludesHelp
HD80:411:CommToolBoxHelp
HD80:411:InsideMacintoshHelp
HD80:411:MPWHelp
HD80:411:PInterfacesHelp
HD80:411:ResourcesHelp
HD80:411:TechNotesHelp
5. Save & Close the Help_Files file
6. Type & select "OpenDoc" in the Worksheet, and choose "Look up" from the 411 menu. A list of OpenDoc help topics will be displayed, and you can then select one of these and choose "Look up" again. You can also directly get help on an OpenDoc class, class::method, type, or constant this way. Repeat as necessary.