| 1 | lttng-ust-dl(3) |
| 2 | =============== |
| 3 | :object-type: library |
| 4 | |
| 5 | |
| 6 | NAME |
| 7 | ---- |
| 8 | lttng-ust-dl - Dynamic linker tracing (LTTng-UST helper) |
| 9 | |
| 10 | |
| 11 | SYNOPSIS |
| 12 | -------- |
| 13 | Launch your application by preloading `liblttng-ust-dl.so`: |
| 14 | |
| 15 | [role="term"] |
| 16 | [verse] |
| 17 | $ *LD_PRELOAD=liblttng-ust-dl.so* my-app |
| 18 | |
| 19 | |
| 20 | DESCRIPTION |
| 21 | ----------- |
| 22 | When the `liblttng-ust-dl.so` library is preloaded before a given |
| 23 | application starts, it causes all calls to man:dlopen(3) and |
| 24 | man:dlclose(3) in said application to be traced with LTTng-UST (see |
| 25 | man:lttng-ust(3)). |
| 26 | |
| 27 | See man:lttng(1) to learn more about how to control LTTng tracing |
| 28 | sessions. |
| 29 | |
| 30 | The following LTTng-UST events are available when using this library: |
| 31 | |
| 32 | `lttng_ust_dl:dlopen`:: |
| 33 | Emitted when man:dlopen(3) is called. |
| 34 | + |
| 35 | Fields: |
| 36 | + |
| 37 | [options="header"] |
| 38 | |============================================================== |
| 39 | | Field name | Description |
| 40 | | `baddr` | Base address of loaded library |
| 41 | | `memsz` | Size of loaded library in memory |
| 42 | | `path` | Path to loaded library file |
| 43 | |============================================================== |
| 44 | |
| 45 | `lttng_ust_dl:dlclose`:: |
| 46 | Emitted when man:dlclose(3) is called. |
| 47 | + |
| 48 | Fields: |
| 49 | + |
| 50 | [options="header"] |
| 51 | |============================================================== |
| 52 | | Field name | Description |
| 53 | | `baddr` | Base address of loaded library |
| 54 | |============================================================== |
| 55 | |
| 56 | `lttng_ust_dl:debug_link`:: |
| 57 | Emitted when debug link information is found when loading a library |
| 58 | with man:dlopen(3). See |
| 59 | https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html[Debugging Information in Separate Files] |
| 60 | for more information about debug links. |
| 61 | + |
| 62 | Fields: |
| 63 | + |
| 64 | [options="header"] |
| 65 | |============================================================== |
| 66 | | Field name | Description |
| 67 | | `baddr` | Base address of loaded library |
| 68 | | `filename` | Debug link file name |
| 69 | | `crc` | Debug link file's CRC |
| 70 | |============================================================== |
| 71 | |
| 72 | `lttng_ust_dl:build_id`:: |
| 73 | Emitted when a build ID is found when loading a library |
| 74 | with man:dlopen(3). See |
| 75 | https://sourceware.org/gdb/onlinedocs/gdb/Separate-Debug-Files.html[Debugging Information in Separate Files] |
| 76 | for more information about build IDs. |
| 77 | + |
| 78 | Fields: |
| 79 | + |
| 80 | [options="header"] |
| 81 | |============================================================== |
| 82 | | Field name | Description |
| 83 | | `baddr` | Base address of loaded library |
| 84 | | `build_id` | Build ID |
| 85 | |============================================================== |
| 86 | |
| 87 | |
| 88 | include::common-footer.txt[] |
| 89 | |
| 90 | include::common-copyrights.txt[] |
| 91 | |
| 92 | include::common-authors.txt[] |
| 93 | |
| 94 | |
| 95 | SEE ALSO |
| 96 | -------- |
| 97 | man:lttng-ust(3), |
| 98 | man:dlopen(3), |
| 99 | man:lttng(1) |