site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com On Nov 12, 2007, at 8:08 PM, Greg Parker wrote: % nm -m /usr/lib/libc.dylib | grep _open ... 00085324 (__TEXT,__text) external _open 000012c8 (__TEXT,__text) external _open$NOCANCEL$UNIX2003 0000be8c (__TEXT,__text) external _open$UNIX2003 Yes, it will. - Kevin _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... bejo wrote: I'm trying to interpose system's open() function with my own using the dyld, I had no problem with that on Tiger, but the same code on Leopard doesn't work any longer. I compile my library this way: gcc -arch ppc -dynamiclib -fno-common -o open_interposer.dylib open_interposer.c and then I run my app this way: DYLD_INSERT_LIBRARIES=open_interposer.dylib DYLD_FORCE_FLAT_NAMESPACE=1 ./my_app and the application is still using system's open() function instead of mine :(. DYLD_PRINT_LIBRARIES=1 shows that pen_interposer.dylib is loaded before other libs. open() is more than meets the eye in Leopard. You may need to interpose more than one entry point. When you type `open(...)` in your C code, one of those symbol names is chosen depending on your compile options (specifically UNIX compliance, in this case). You can use `nm -m` on your app to see which version it's linking to. For example, a trivial 32-bit i386 test program built on Leopard with `cc` and no other options uses _open$UNIX2003. Good point. Be sure to include the appropriate header files so that you get the $UNIX2003 magic. Relying on implicit function declarations will not work. (I don't know whether function interposing still works the way you want even after working around this change.) This email sent to site_archiver@lists.apple.com