Help linking a C program to .oct files

[Jerry]

I'm use OS X 10.9.4 and I'm trying to link a C program* to one of Octave's 
"loadable functions," specifically the modified Bessel function of the second 
kind which, using nm, appears to be on my machine at

/opt/local/lib/octave/3.6.4/oct/x86_64-apple-darwin13.3.0/besselj.oct 

I'm not having any luck even though the octave documentation at 

http://octave.sourceforge.net/coda/c58.html

says they are shared libraries.

I have successfully linked and bound to other Octave functions but of the 
"built-in" type (at /opt/local/lib/octave/3.6.4/liboctave.dylib) so I feel that 
linking to these loadable functions should be possible too.

At one point I got the complaint that 

ld: can't link with bundle (MH_BUNDLE) only dylibs (MH_DYLIB) file 
'/opt/local/lib/octave/3.6.4/oct/x86_64-apple-darwin13.3.0//libbesselj.dylib' 
for architecture x86_64 

which somehow prompted me to try

$ otool -hv besselj.oct 
besselj.oct: 
Mach header 
      magic cputype cpusubtype  caps    filetype ncmds sizeofcmds      flags 
MH_MAGIC_64  X86_64        ALL  0x00      BUNDLE    21       2128   NOUNDEFS 
DYLDLINK TWOLEVEL WEAK_DEFINES BINDS_TO_WEAK 

At this point I'm in way over my head.

Does anyone have any idea what is in these .oct files and if it is possible to 
link to them? I suppose I could try compiling from source into a more familiar 
library....

Jerry

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*Not really C but Ada (gcc Ada aka GNAT) using C calling conventions.