ADRIAN@vax.oxford.ac.uk (11/06/90)
I forgot to say that it is unsafe to use the file utility set in general, and for identifying "orphans" in particular, if you have any 'host' files in the tree attached to your folds. This needs a little more explanation. In TDS3, supported files are in TDS folded format. You can use the file utilities to read in at least arbitrary text host files. That process produces a TDS format image, and is quite safe. In TDS3, you may discover some unsupported extensions that allow ordinary `flat` text files, in particular those used by Toolset products, to be treated as if they were folded. But the files remain in non-TDS format, and this is only partially supported. Such files will in general appear as a filed fold with a header ...H (some text.) Only a subset of the TDS3 will handle such files correctly: the user filer, for example does not support them. The filer utility package can fail badly if you apply it to folds which have nested folds of type ...H. After a few nasty experiences, I have adopted the discipline of only using ...H files in special directories where I want to use the superb TDS folding editor on Toolset files (and indeed as a general text editor). Let me summarize for emphasis: 1) If you are using the TDS3 in the supported fashion, there is no problem. You will not be able to create ...H files, and you probably be unaware of their potential existance. 2) If you want to extend the TDS3 style of editing to general purpose 'flat' host files, and have discovered the secret, then you will know and love ...H host files. Then you need to be careful in the use of the File Handling package: Attach is OK. See Appendix G of the manual for the internal formats of TDS (G.1) and of (some) `flat` files (G.2) -------------------------------------------------------------------------- I think this is substantially correct, but I have not on this occasion checked with Inmos experts: I thought that it was urgent to warn you not to follow my previous advice if you had embedded ...H files : the consequences can be extremely nasty, particularly with undeserving orphans, and the loss of text.... ------------------------------------------------------------------ Adrian Lawrence. Oxford University Microprocessor Unit. Adrian @ uk.ac.oxord.vax