[Sbcl-help] How can I tell which foreign function symbols are callable?

[John M. <jm...@ma...>]

Hi;

Short Version: How can I tell what foreign symbols are "undefined"
even though they have addresses?

* (SB-SYS:GET-DYNAMIC-FOREIGN-SYMBOL-ADDRESS "_ZNSt9exceptionC1Ev")
STYLE-WARNING: Undefined alien: "_ZNSt9exceptionC1Ev"

134553364
*

Longer Version: GCCXML emits records for everything, including the
above (constructor for std::exception).  However, when I try to
define-alien-routine, it errors.  What's the right way to "sniff"
foreign symbols before I generate any errors by attempting to
define-alien-routine them?  Something of the form:

(zerop (sap-int (dlsym *runtime-dlhandle* "_ZNSt9exceptionC1Ev")))

T

How do I get the right *runtime-dlhandle* when I'm loading or I have
loaded multiple shared libraries?

Thanks,

-jm

-- 
==== John Morrison
==== MAK Technologies Inc.
==== 10 Fawcett Street, Cambridge, MA 02138
==== http://www.mak.com/
==== vox:617-876-8085 x115
==== fax:617-876-9208
==== jm...@ma...