[Simh] Attach tar to tape device and access it from v7 in simh

[Lars Brinkhoff]

Johnny Billquist wrote:
> Lars Brinkhoff wrote:
>> Johnny Billquist wrote:
>>> I bet that would be written in some ANSI C, for which you won't find
>>> a C compiler for V7...
>> GCC has a PDP-11 backend, so maybe you can cross compile it.
> That would depend on if calling conventions, register conventions,
> a.out format and so on are compatible between V7 and whatever format
> gcc uses.

Right, it depends on a lot of things.  GCC says it targets BSD, unknown
version.  I don't know whether that's compatible with V7.  There also
seems to be PDP-11 backends for PCC and LCC.  The former targets
2.11BSD.

I mostly just wanted to point out that there may be, or might not be far
from, an ANSI C compiler for V7.

> Not to mention you also need all the V7 libraries where you do the
> cross compile.

In this case I would just copy the assembly language output file to the
target system, and build it there.  So not pure cross compilation.

It could be that the software uses lots of definitions and calls which
aren't supported in the V7 libraries.  Or that it's too bloated to fit
in a PDP-11.