On Sun, 17 Oct 2010, Wolfgang Schuster wrote:

>
> Am 17.10.2010 um 19:58 schrieb Aditya Mahajan:
>
>> I wanted something that will work consistently in MkII and MkIV. I can do:
>>
>> \doifmodeelse{\s!mkii}
>>  {\let\ReadFilter\ReadFile}
>>  {\def\ReadFilter#1{\doreadfile{any}\empty{#1}\donothing\donothing}}
>>
>> but, I wanted to avoid such things if possible :-/
>
> Does this work:
>
> \def\ReadFilter#1%
>  {\readsetfile{/tmp/}{#1}\donothing\donothing}

Yes, for both MkII and MkIV. But this still does not fit the requirement 
of my module.

\setupexternalfilters
   [directory=,
    outputfile=~/output/\externalfilterinputfile.tex,
    readcommand=\ReadFilter]

will fail. (The above will generate all the *-*.tmp files in current 
directory, which can be purged by passing --purge. The output files are 
generated in ~/output directory for future reference. But \ReadFilter 
cannot read the file.

I think that I will go with separate definitions for MkII and MkIV, or 
perhaps even redefine \ReadFile just before the read function is defined.

>> (BTW, why is system mode *mkii not set in MkII?)
>
> Maybe Hans forgot it for mkii but it doesn’t matter whether mkii/mkiv is a normal mode or a system mode.

IIRC, system modes cannot be reset using \(enable|disable)mode.

Aditya