Function interposition in Linux without dlsym

Question

I\'m currently working on a project where I need to track the usage of several system calls and low-level functions like mmap, brk, sbrk

Answer 1

You can examine function invocation unobtrusively using tools such as:

• gdb
• ltrace
• systemtap

These tools allow a monitor program to inform you when a function is called, and allow you to interrogate the arguments.

The main differences are:

• gdb is interactive, but powerful
• ltrace simple to use, but you can only print the function name
• systemtap is not interactive, but it can be very fast, and is powerful.