[coyotos-dev] IDL compatibility

[Charles Landau]

At 10:54 AM -0400 6/18/07, Jonathan S. Shapiro wrote:
>On Sun, 2007-06-17 at 12:08 +0200, Valerio Bellizzomi wrote:
>>  On 16/06/2007, at 18.53, Charles Landau wrote:
>>
>>  >To the extent that Coyotos and CapROS have similar objects, it would
>>  >be very good if programs that use those objects were compatible
>>  >across the two systems. Both systems use IDL, so differences in the
>>  >details of how you invoke a capability are probably not an issue.
>>  >
>>  >Because Coyotos packages are all under the namespace "coyotos",
>>  >procedures to call an object such as the spacebank will have names
>  > >like "coyotos_spacebank_alloc". In CapROS the corresponding procedure
>>  >names begin with "eros" (or perhaps "capros"). So even if the
>>  >semantics matches, the procedure names of every key invocation would
>>  >have to be changed to move a program from one system to another. Not
>>  >exactly a good compatibility story.
>>  >
>>  >Is there a better way?
>>
>>  Use a "system" namespace, we would have "system_spacebank_alloc"
>>  everywhere.
>
>Yes, calls to the spacebank methods in coyotos will begin with coyotos_.
>This is intentional and necessary. The two systems do not implement
>identical interfaces, and it is therefore not appropriate or desirable
>for them to use the same method namespace. Quite the contrary: if there
>is to be ANY hope at all of cross-compatibility, it is *imperative* that
>these name spaces not overlap.
>
>  PLEASE do NOT switch to something like "system_".

So, thinking about how you would port a program, say from Coyotos to 
CapROS, without major rewriting:
In cases where methods are identical (and there will be some), you could

#include <coyotosCompatibility.h>

which contains for example

#define coyotos_spacebank_alloc capros_spacebank_alloc
(or better, define coyotos_spacebank_alloc as an inline function that 
calls capros_spacebank_alloc)

Is this what you have in mind?