doc/man/man3/dladdr.3

   1 .Dd September 24, 2004
   2 .Os
   3 .Dt DLADDR 3
   4 .Sh NAME
   5 .Nm dladdr
   6 .Nd find the image containing a given address
   7 .Sh SYNOPSIS
   8 .In dlfcn.h
   9 .Ft int
  10 .Fn dladdr "const void* addr" "Dl_info* info"
  11 .Sh DESCRIPTION
  12 The
  13 .Fn dladdr
  14 function
  15 queries dyld (the dynamic linker) for information about the image
  16 containing the address
  17 .Fa addr .
  18 The information is returned in the structure specified by
  19 .Fa info .
  20 The structure contains at least the following members:
  21 .Bl -tag -width "XXXconst char *dli_fname"
  22 .It Li "const char* dli_fname"
  23 The pathname of the shared object containing the address.
  24 .It Li "void* dli_fbase"
  25 The base address (mach_header) at which the image is mapped into the
  26 address space of the calling process.
  27 .It Li "const char* dli_sname"
  28 The name of the nearest run-time symbol with a value less than or
  29 equal to
  30 .Fa addr .
  31 .It Li "void* dli_saddr"
  32 The value of the symbol returned in
  33 .Li dli_sname .
  34 .El
  35 .Pp
  36 The
  37 .Fn dladdr
  38 function
  39 is available only in dynamically linked programs.
  40 .Sh ERRORS
  41 If an image containing
  42 .Fa addr
  43 cannot be found,
  44 .Fn dladdr
  45 returns 0.
  46 On success, a non-zero value is returned.
  47 .Pp
  48 If the image containing
  49 .Fa addr
  50 is found, but no nearest symbol was found,
  51 the dli_sname and dli_saddr fields are set to NULL.
  52 .Sh SEE ALSO
  53 .Xr dyld 3 ,
  54 .Xr dlopen 3
  55 .Sh HISTORY
  56 The
  57 .Fn dladdr
  58 function first appeared in the Solaris operating system.
  59 .Sh AUTHORS
  60 Mac OS X 10.3 incorporated the dlcompat package written by Jorge Acereda <jacereda@users.sourceforge.net>
  61 and Peter O'Gorman <ogorman@users.sourceforge.net>.
  62 .Pp
  63 In Mac OS X 10.4, dlopen was rewritten to be a native part of dyld.
  64 .Pp
  65 This man page was borrowed from FreeBSD and modified.
  66 .Sh BUGS
  67 This implementation is almost bug-compatible with the Solaris
  68 implementation.  The following bugs are present:
  69 .Bl -bullet
  70 .It
  71 Returning 0 as an indication of failure goes against long-standing
  72 Unix tradition.
  73 .El