Build system: implement REUSE with SPDX identifiers

[lttng-ust.git] / src / lib / lttng-ust-libc-wrapper / README.md

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+<!--
+SPDX-FileCopyrightText: 2023 EfficiOS, Inc.
+
+SPDX-License-Identifier: CC-BY-4.0
+-->
+
+# LTTng-UST libc wrapper
+
+`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.