dladdr(3C)																dladdr(3C)

NAME

       dladdr, dladdr1 - translate address to symbolic information

SYNOPSIS

       #include <dlfcn.h>

       int dladdr(void *address, Dl_info *dlip);

       int dladdr1(void *address, Dl_info *dlip, void **info, int flags);

       The  dladdr()  and dladdr1() functions determine if the specified address is located within one of the mapped objects that make up the cur-
       rent applications address space. An address is deemed to fall within a mapped object when it is between the  base  address,  and  the  _end
       address	of  that object. See . If a mapped object fits this criteria, the symbol table made available to the runtime linker is searched to
       locate the nearest symbol to the specified address.  The nearest symbol is one that has a value less than or equal to the required address.

       The Dl_info structure must be preallocated by the user. The structure members are filled in by dladdr(), based on  the  specified  address.
       The Dl_info structure includes the following members:

       const char *   dli_fname;
       void *	      dli_fbase;
       const char *   dli_sname;
       void *	      dli_saddr;

       The Dl_info members provide the following information.

       dli_fname       Contains a pointer to the filename of the containing object.

       dli_fbase       Contains the base address of the containing object.

       dli_sname       Contains  a  pointer  to  the symbol name that is nearest to the specified address. This symbol either represents the exact
		       address that was specified, or is the nearest symbol with a lower address.

       dli_saddr       Contains the actual address of the symbol pointed to by dli_sname.

       The dladdr1() function provides for addition information to be returned as specified by the flags argument:

       RTLD_DL_SYMENT	       Obtain the ELF symbol table entry for the matched symbol. The info argument points to a symbol pointer  as  defined
			       in <sys/elf.h> (Elf32_Sym **info or Elf64_Sym **info).

       RTLD_DL_LINKMAP	       Obtain the Link_map for the matched file. The info argument points to a Link_map pointer as defined in <sys/link.h>
			       (Link_map **info).

       If the specified address cannot be matched to a mapped object, a 0 is returned. Otherwise, a non-zero return is	made  and  the	associated
       Dl_info elements are filled.

       The  dladdr()  and dladdr1() functions are one of a family of functions that give the user direct access to the dynamic linking facilities.
       These facilities are available to dynamically-linked processes only. See .

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       ld(1), dlclose(3C), dldump(3C), dlerror(3C), dlopen(3C), dlsym(3C), attributes(5)

       The Dl_info pointer elements point to addresses within the mapped objects. These pointers can become invalid if objects are  removed  prior
       to these elements use. See dlclose(3C).

       If no symbol is found to describe the specified address, both the dli_sname and dli_saddr members are set to 0.

       If  an  object  is  acting  as  a  filter, care should be taken when interpreting the address of any symbol obtained using a handle to this
       object. For example, using dlsym(3C) to obtain the symbol _end for this object, results in returning the address of the symbol _end  within
       the filtee, not the filter. For more information on filters see the .

								    26 Sep 2005 							dladdr(3C)