For people interested in manipulating running binary programs, you might also check out the dyninst-api tools developed by the Paradyn project at the Universities of Wisconsin and Maryland. The Paradyn project has been developing runtime code patching tools since 1993. The dyninst API library allows you to patch code into a running program on a wide variety of platforms, including x86 Linux, SPARC Solaris, AIX, x86 Windows, Compaq Alpha, and SGI Irix. IA64 is coming soon. Code to be inserted is specified in a machine-independent "Abstract Syntax Tree" (AST) format and then the platform-specific code generators handle thed details. Code can be inserted and removed at will. The AST's can include all the expected C-like expressions, if-then-else, function calls, and other operations. From the tool using dyninst, you can cause libraries to be loaded, functions to be called one, remove function calls, redirect calls at individual function call sites or enter functions. Paradyn is a parallel performance profiling tool built on the dyninst technology (with all sorts of cool analysis features). The source and binary are freely distributed. For more information, check out www.dyninst.org, www.paradyn.org, or mail us at paradyn@cs.wisc.edu. We also have a kernel profiling tools for Solaris (Linux coming soon), that allows you to profiling almost *anything* inside the kernel. --bart miller professor computer sciences university of wisconsin
