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

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# 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.
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	2	SPDX-FileCopyrightText: 2023 EfficiOS, Inc.
	3
	4	SPDX-License-Identifier: CC-BY-4.0
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	6
	7	# LTTng-UST libc wrapper
	8
	9	`liblttng-ust-libc` is used for instrumenting some calls to libc in a program,
	10	without need for recompiling it.
	11
	12	This library defines a `malloc()` function that is instrumented with a
	13	tracepoint. It also calls the libc `malloc()` afterwards. When loaded with
	14	LD\_PRELOAD, it replaces the libc `malloc()` function, in effect instrumenting
	15	all calls to `malloc()`. The same is performed for `free()`.
	16
	17	See the "run" script for a usage example.