extern "C" and C++ files

Gray Alien

These are the "restrictio ns" I have come accross when "wrapping up" all
function declarations in a header with extern "C":

i). Inability to overload functions in exposed API
ii). Inability to include (template?) classes (e.g. string) in exposed API

Are there other ex/implicit restrictions I may have missed ?

Jun 30 '07 #1

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1385

Alan Woodland

Gray Alien wrote:

These are the "restrictio ns" I have come accross when "wrapping up" all
function declarations in a header with extern "C":

i). Inability to overload functions in exposed API
ii). Inability to include (template?) classes (e.g. string) in exposed API

Are there other ex/implicit restrictions I may have missed ?

I'd guess bool wouldn't be portably usable too? and one would assume
references can't be exposed to a C compiler either?

Alan

Jun 30 '07 #2

James Kanze

On Jun 30, 4:04 pm, Alan Woodland <a...@aber.ac.u kwrote:

Gray Alien wrote:
These are the "restrictio ns" I have come accross when "wrapping up" all
function declarations in a header with extern "C":

i). Inability to overload functions in exposed API
ii). Inability to include (template?) classes (e.g. string) in exposed API

Are there other ex/implicit restrictions I may have missed ?

I'd guess bool wouldn't be portably usable too? and one would assume
references can't be exposed to a C compiler either?

At the interface level, obviously, `extern "C"' doesn't make
much sense unless you stick to the common subset of C and C++.
(I would imagine that most, if not all, implementations , will
also make bool compatible with the C99 boolean type, and I can't
imagine an implementation where complex wasn't compatible with
it's C equivalents. But I don't think that the standards
guarantee this anywhere, and I'm not even sure how one would
formulate such guarantees.)

--
James Kanze (Gabi Software) email: ja*********@gma il.com
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Jul 1 '07 #3

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