contents/using-lttng/instrumenting/c-application/intro.md

   1 ---
   2 id: c-application
   3 ---
   4
   5 Instrumenting a C (or C++) application, be it an executable program or
   6 a library, implies using LTTng-UST, the
   7 user space tracing component of LTTng. For C/C++ applications, the
   8 LTTng-UST package includes a dynamically loaded library
   9 (`liblttng-ust`), C headers and the `lttng-gen-tp` command line utility.
  10
  11 Since C and C++ are the base languages of virtually all other
  12 programming languages
  13 (Java virtual machine, Python, Perl, PHP and Node.js interpreters, etc.),
  14 implementing user space tracing for an unsupported language is just a
  15 matter of using the LTTng-UST C API at the right places.
  16
  17 The usual work flow to instrument a user space C application with
  18 LTTng-UST is:
  19
  20   1. Define tracepoints (actual probes)
  21   2. Write tracepoint providers
  22   3. Insert tracepoints into target source code
  23   4. Package (build) tracepoint providers
  24   5. Build user application and link it with tracepoint providers
  25
  26 The steps above are discussed in greater detail in the following
  27 subsections.