On 11 Jan 2005 at 22:19, Rich Mellor wrote: (...)1) Older programs which would expect (a6,a5) to point to the command
string at the top of the data area. If we were to adopt this scheme, then
a lot of existing programs would immediately not be able to get at any
parameters passed to them. We do not have the software authors or sources
to enable us to amend existing programs or re-write them. I guess we
could overcome this by amending the setup job code to have (A5,A0) (?)
point to the location of the home directory
No. Let a6,a5 point to where it usually points, i.e. the command string. Finding
the home dir after the command string (for a prog aware of this) is trivial.
I agree that (a6,a5) MUST point to the command string - otherwise existing programs may have a problem on the new system as they will expect the command string to be here not a little bit further down the stack.
Only problem here is that if an existing program is called with the home dir on the stack - the program will not tidy up the stack correctly since it does not know to remove the extra bytes.... (I think though could be wrong here)
However, how would a program aware that the home dir might be higher up the stack cope with this - for example, some programs MAY require an empty string to be passed as the command string. Guess if there is a special identifier word before the home dir string, this would overcome this problem.
2) The bigger problem and one which is harder to address... How do you decide what is the home directory of a file called win1_basic_exts_turbo_config_exe
Simple. Open_dir win1_basic_exts_turbo_config_exe. Get the name of the resulting file. This will be the directory name (!).
OK - thanks to everyone I had forgotten about FNAME$
-- Rich Mellor RWAP Services 26 Oak Road, Shelfield, Walsall, West Midlands WS4 1RQ
http://www.rwapservices.co.uk/
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