linux, LD_PRELOAD error

i am new in programming under linux and trying to get working this code: http://scaryreasoner.wordpress.com/2007/11/17/using-ld_preload-libraries-and-glibc-backtrace-function-for-debugging/

but getting error: "ERROR: ld.so: object 'libwrap_ioctl.so' from LD_PRELOAD cannot be preloaded: ignored."

what can cause it? system - Archlinux, kernel 2.6.32

thank you for answers

upd1: "Check with ldd libwrap_ioctl.so if some dependency of this library is missing."

checked. no开发者_JS百科, i have all needed libraries

If your program is 32-bit, be sure that your library is also 32-bit, or if your program is 64-bit, be sure that your library is 64-bit. You can check this with the file command.

Also if the library is not in the library search path, be sure to specify a path even if it is in the current directory. With no path it will look for the library using the library search path. If the library is in the current directory you can use LD_PRELOAD=./libwrap_ioctl.so. You can debug library search issues by setting LD_DEBUG=libs.