DLADDR(3)

NAME
dladdr - find the image containing a given address

SYNOPSIS
#include <dlfcn.h>
int
dladdr(const void* addr, Dl_info* info);

DESCRIPTION
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.

ERRORS
If an image containing addr cannot be found, dladdr() returns 0. On success, 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.

SEE ALSO
dyld(3), dlopen(3)

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

AUTHORS
Mac OS X 10.3 incorporated the dlcompat package written by Jorge Acereda <jacereda@users.sourceforge.net> and Peter O'Gorman <ogorman@users.sourceforge.net>.

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.

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

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