The eresi tracer is an embedded tracer which operates directly from within the traced the binary itself. we acheive this modus operandi by using binary module injection and function redirection. a new binary is created where all functions are hooked so we can display the program entering and leaving functions. as the tracer is directly into the traced binary, we gain performance as we don't need to single-step, in comparison with others tracers relying on a kernel interface like its ptrace debugging api. another major difference is that etrace works on all functions without using a predefined list, as done by most other tracers. etrace was designed for reverse engineering targets with not only glibc functions, but also a custom function present in your binary or in a specific library.

the main features of the elf tracer (etrace) are :

* command-line tracing on elf binaries without using ptrace.
* a logical organization of trace events fully integrated in the scripting
language.
* support debug format information (if available) to display names and types
of function parameters.
* advanced user control over selection of traced functions with regular
expressions.