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33 .Nd find the shared object containing a given address
39 .Fn dladdr "const void *addr" "Dl_info *info"
42 queries the dynamic linker for information about the shared object
43 containing the address
45 The information is returned in the structure specified by
47 The structure contains at least the following members:
48 .Bl -tag -width "XXXconst char *dli_fname"
49 .It Li "const char *dli_fname"
50 The pathname of the shared object containing the address.
51 .It Li "void *dli_fbase"
52 The base address at which the shared object is mapped into the
53 address space of the calling process.
54 .It Li "const char *dli_sname"
55 The name of the nearest run-time symbol with a value less than or
58 When possible, the symbol name is returned as it would appear in C
61 If no symbol with a suitable value is found, both this field and
65 .It Li "void *dli_saddr"
66 The value of the symbol returned in
71 is available only in dynamically linked programs.
73 If a mapped shared object containing
78 In that case, a message detailing the failure can be retrieved by
82 On success, a non-zero value is returned.
89 function first appeared in the Solaris operating system.
91 This implementation is bug-compatible with the Solaris
92 implementation. In particular, the following bugs are present:
97 lies in the main executable rather than in a shared library, the
100 may not be correct. The pathname is taken directly from
102 of the calling process. When executing a program specified by its
103 full pathname, most shells set
105 to the pathname. But this is not required of shells or guaranteed
106 by the operating system.
114 is a global function, its value may be an unpleasant surprise. In
115 dynamically linked programs, the address of a global function is
116 considered to point to its program linkage table entry, rather than to
117 the entry point of the function itself. This causes most global
118 functions to appear to be defined within the main executable, rather
119 than in the shared libraries where the actual code resides.
121 Returning 0 as an indication of failure goes against long-standing