I'm wanting to write a replacement C function for a few different glibc calls for debugging purposes, and other uses as well. The functions in mind are small, including straight kernel syscalls, etc.. I'm looking at the glibc source and it goes way over my head. Some of the functions appear to contain no code whatsoever, and are marked up with odd stuff I've never seen before, particularly in the sysdeps/generic/ directory, but in others as well... When you call a given glibc function, in particular one that maps direct to a syscall, how do you intercept it via ldpreload, and how do you build the .so file properly without trashing something? If someone could give me an example of overriding the built in getpid() call for example to do what it does, but to also open a file "/tmp/getpid-test" and write out the date and time stamp, as well as the executable program's full path that called getpid(), it would give me something to go on... Preferably I'd like examples, either direct, or pointers to some downloadable easy to understand code that shows interception of a general C library call, how to replace it, or chain to/through it, as well as interception of a kernel system call through the C library and how to replace it or chain to/through it. Any help would be greatly appreciated. Thanks, TTYL -- Mike A. Harris Linux advocate Computer Consultant GNU advocate Capslock Consulting Open Source advocate Be up to date on nerd news and stuff that matters: http://slashdot.org _______________________________________________ Redhat-devel-list mailing list [EMAIL PROTECTED] https://listman.redhat.com/mailman/listinfo/redhat-devel-list
