[lttng-docs.git] / contents / using-lttng / instrumenting / c-application / building-linking / using-lttng-ust-with-daemons.md

---
id: using-lttng-ust-with-daemons
---

Some extra care is needed when using `liblttng-ust` with daemon
applications that call `fork()`, `clone()` or BSD's `rfork()` without
a following `exec()` family system call. The `liblttng-ust-fork`
library must be preloaded for the application.

Example:

<pre class="term">
<strong>LD_PRELOAD=liblttng-ust-fork.so</strong> ./app
</pre>

Or, if you're using a tracepoint provider shared library:

<pre class="term">
<strong>LD_PRELOAD="liblttng-ust-fork.so /path/to/tp.so"</strong> ./app
</pre>
Commit	Line	Data
5e0cbfb0 PP	1	---
	2	id: using-lttng-ust-with-daemons
	3	---
	4
	5	Some extra care is needed when using `liblttng-ust` with daemon
	6	applications that call `fork()`, `clone()` or BSD's `rfork()` without
	7	a following `exec()` family system call. The `liblttng-ust-fork`
	8	library must be preloaded for the application.
	9
	10	Example:
	11
	12	<pre class="term">
	13	<strong>LD_PRELOAD=liblttng-ust-fork.so</strong> ./app
	14	</pre>
	15
	16	Or, if you're using a tracepoint provider shared library:
	17
	18	<pre class="term">
	19	<strong>LD_PRELOAD="liblttng-ust-fork.so /path/to/tp.so"</strong> ./app
	20	</pre>