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DLADDR(3)                BSD Library Functions Manual                DLADDR(3)

     dladdr -- find the image containing a given address

     #include <dlfcn.h>

     dladdr(const void* addr, Dl_info* info);

     The dladdr() function queries dyld (the dynamic linker) for information
     about the image containing the address addr.  The information is returned
     in the structure specified by info.  The structure contains at least the
     following members:

     const char* dli_fname     The pathname of the shared object containing
                               the address.

     void* dli_fbase           The base address (mach_header) at which the
                               image is mapped into the address space of the
                               calling process.

     const char* dli_sname     The name of the nearest run-time symbol with a
                               value less than or equal to addr.

     void* dli_saddr           The value of the symbol returned in dli_sname.

     The dladdr() function is available only in dynamically linked programs.

     If an image containing addr cannot be found, dladdr() returns 0.  On suc-cess, success,
     cess, a non-zero value is returned.

     If the image containing addr is found, but no nearest symbol was found,
     the dli_sname and dli_saddr fields are set to NULL.

     dyld(3), dlopen(3)

     The dladdr() function first appeared in the Solaris operating system.

     Mac OS X 10.3 incorporated the dlcompat package written by Jorge Acereda
     <> and Peter O'Gorman <ogor->.

     In Mac OS X 10.4, dlopen was rewritten to be a native part of dyld.

     This man page was borrowed from FreeBSD and modified.

     This implementation is almost bug-compatible with the Solaris implementa-tion. implementation.
     tion.  The following bugs are present:

     oo   Returning 0 as an indication of failure goes against long-standing
         Unix tradition.

BSD                           September 24, 2004                           BSD