lttng-ust-dl(3)
===============
:object-type: library
NAME
----
lttng-ust-dl - Dynamic linker tracing (LTTng-UST helper)
SYNOPSIS
--------
Launch your application by preloading `liblttng-ust-dl.so`:
[role="term"]
[verse]
*LD_PRELOAD=liblttng-ust-dl.so* my-app
DESCRIPTION
-----------
When the `liblttng-ust-dl.so` library is preloaded before a given
application starts, it causes all calls to man:dlopen(3) and
man:dlclose(3) in said application to be traced with LTTng-UST (see
man:lttng-ust(3)).
See man:lttng(1) to learn more about how to control LTTng tracing
sessions.
The following LTTng-UST events are available when using this library:
`lttng_ust_dl:dlopen`::
Emitted when man:dlopen(3) is called.
+
Fields:
+
[options="header"]
|==============================================================
| Field name | Description
| `baddr` | Base address of loaded library
| `memsz` | Size of loaded library in memory
| `path` | Path to loaded library file
|==============================================================
`lttng_ust_dl:dlclose`::
Emitted when man:dlclose(3) is called.
+
Fields:
+
[options="header"]
|==============================================================
| Field name | Description
| `baddr` | Base address of loaded library
|==============================================================
`lttng_ust_dl:debug_link`::
Emitted when debug link information is found when loading a library
with man:dlopen(3). See
https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html[Debugging Information in Separate Files]
for more information about debug links.
+
Fields:
+
[options="header"]
|==============================================================
| Field name | Description
| `baddr` | Base address of loaded library
| `filename` | Debug link file name
| `crc` | Debug link file's CRC
|==============================================================
`lttng_ust_dl:build_id`::
Emitted when a build ID is found when loading a library
with man:dlopen(3). See
https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html[Debugging Information in Separate Files]
for more information about build IDs.
+
Fields:
+
[options="header"]
|==============================================================
| Field name | Description
| `baddr` | Base address of loaded library
| `build_id` | Build ID
|==============================================================
include::common-footer.txt[]
include::common-copyrights.txt[]
include::common-authors.txt[]
SEE ALSO
--------
man:lttng-ust(3),
man:dlopen(3),
man:lttng(1)