liblttng-ust-libc is used for instrumenting some calls to libc in a
program, without need for recompiling it.
This library defines a malloc() function that is instrumented with a
tracepoint. It also calls the libc malloc afterwards. When loaded with
LD_PRELOAD, it replaces the libc malloc() function, in effect
instrumenting all calls to malloc(). The same is performed for free().
See the "run" script for a usage example.