TRACELOG(3)

💖 TRACELOG(3) — LTTng Manual 💖

okay bestie, this is the TRACELOG(3) page from the LTTng Manual. It's giving "logging macro with a log level" and we're gonna keep every detail, fr fr. ✨

🌸 NAME 🌸

tracelog — LTTng-UST printf(3)-like interface with a log level.

✨ SYNOPSIS ✨

#include <lttng/tracelog.h>

#define tracelog(level, fmt, ...)

Link with -llttng-ust -llttng-ust-common.

🦋 DESCRIPTION 🦋

The tracelog() macro is part of version 0 of the LTTng-UST API (see the “Compatibility with previous APIs” section of lttng-ust(3)).

Prefer using lttng_ust_tracelog(3) — it's part of version 1 of the API and has the lttng_ust_ namespace. periodt. 💅

💀 BUGS 💀

If you encounter any issue or usability problem, please report it on the LTTng bug tracker https://bugs.lttng.org/projects/lttng-ust. No gatekeeping, bestie. 🫶

🌈 RESOURCES 🌈

• LTTng project website http://lttng.org
• LTTng documentation http://lttng.org/docs
• Git repositories http://git.lttng.org
• GitHub organization http://github.com/lttng
• Continuous integration http://ci.lttng.org/
• Mailing list http://lists.lttng.org for support and development: lttng-dev@lists.lttng.org
• IRC channel irc://irc.oftc.net/lttng: #lttng on irc.oftc.net

👑 COPYRIGHTS 👑

This macro is part of the LTTng-UST project.

This macro is distributed under the GNU Lesser General Public License, version 2.1 http://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html. See the COPYING file https://github.com/lttng/lttng-ust/blob/v2.16/COPYING for more details.

🫶 THANKS 🫶

Thanks to Ericsson for funding this work, providing real-life use cases, and testing. 💖

Special thanks to Michel Dagenais and the DORSAL laboratory http://www.dorsal.polymtl.ca/ at École Polytechnique de Montréal for the LTTng journey. 🌸

🧚 AUTHORS 🧚

LTTng-UST was originally written by Mathieu Desnoyers, with additional contributions from various other people. It is currently maintained by Mathieu Desnoyers <mailto:mathieu.desnoyers@efficios.com>. 👑

⭐ SEE ALSO ⭐

lttng_ust_tracelog(3), lttng_ust_vtracelog(3)

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LTTng 2.16.0 · 08/31/2026 — that's the source/version and date, bestie. byeee 🫶💅