1BABELTRACE2-QUERY(1) Babeltrace 2 manual BABELTRACE2-QUERY(1)
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6 babeltrace2-query - Query an object from a Babeltrace 2 component class
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9 babeltrace2 [GENERAL OPTIONS] query [--params=PARAMS]
10 COMP-CLS-TYPE.PLUGIN-NAME.COMP-CLS-NAME OBJECT
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13 The query command queries the object named OBJECT from the component
14 class named COMP-CLS-NAME of the type COMP-CLS-TYPE found in the
15 Babeltrace 2 plugin named PLUGIN-NAME and prints the results.
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17 See babeltrace2-intro(7) to learn more about the Babeltrace 2 project
18 and its core concepts.
19
20 The available values for COMP-CLS-TYPE are:
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22 source, src
23 Source component class.
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25 filter, flt
26 Filter component class.
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28 sink
29 Sink component class.
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31 The exact object names and the parameters that a given component class
32 expects are described in its own documentation. babeltrace2-help(1) can
33 generally provide this information.
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35 You can use the --params option to pass parameters to the component
36 class’s query operation.
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38 The output of the query command can look like YAML (see
39 <https://yaml.org/>), but it’s not guaranteed to be YAML-compliant.
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41 See “EXAMPLES” for usage examples.
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44 General
45 You can use those options before the command name.
46
47 See babeltrace2(1) for more details.
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49 -d, --debug
50 Legacy option: this is equivalent to --log-level=TRACE.
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52 -l LVL, --log-level=LVL
53 Set the log level of all known Babeltrace 2 loggers to LVL.
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55 --omit-home-plugin-path
56 Do not search for plugins in $HOME/.local/lib/babeltrace2/plugins.
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58 --omit-system-plugin-path
59 Do not search for plugins in /usr/local/lib/babeltrace2/plugins.
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61 --plugin-path=PATH[:PATH]...
62 Add PATH to the list of paths in which plugins can be found.
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64 -v, --verbose
65 Legacy option: this is equivalent to --log-level=INFO.
66
67 Query parameters
68 -p PARAMS, --params=PARAMS
69 Set the query parameters to PARAMS.
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71 The format of PARAMS is a comma-separated list of NAME=VALUE
72 assignments:
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74 NAME=VALUE[,NAME=VALUE]...
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76 NAME
77 Parameter name (C identifier plus the :, ., and - characters).
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79 VALUE
80 One of:
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82 • null, nul, NULL: null value.
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84 • true, TRUE, yes, YES: true boolean value.
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86 • false, FALSE, no, NO: false boolean value.
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88 • Binary (0b prefix), octal (0 prefix), decimal, or
89 hexadecimal (0x prefix) unsigned (with + prefix) or signed
90 64-bit integer.
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92 • Double precision floating point number (scientific notation
93 is accepted).
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95 • Unquoted string with no special characters, and not
96 matching any of the null and boolean value symbols above.
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98 • Double-quoted string (accepts escape characters).
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100 • Array, formatted as an opening [, a comma-separated list of
101 VALUE, and a closing ].
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103 • Map, formatted as an opening {, a comma-separated list of
104 NAME=VALUE assignments, and a closing }.
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106 You may put whitespaces around the individual = (assignment), ,
107 (separator), [ (array beginning), ] (array end), { (map
108 beginning), and } (map end) characters.
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110 Example:
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112 --params='many=null, fresh=yes, condition=false, squirrel=-782329,
113 play=+23, observe=3.14, simple=beef,
114 needs-quotes="some string",
115 escape.chars-are:allowed="a \" quote",
116 things=[1, "hello", 2.71828],
117 frog={slow=2, bath=[bike, 23], blind=NO}'
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119 Important
120 Like in the example above, make sure to single-quote the whole
121 argument when you run this command from a shell, as it can
122 contain many special characters.
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124 Command information
125 -h, --help
126 Show the command’s help and quit.
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129 Example 1. Query the available tracing sessions of a local LTTng relay
130 daemon.
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132 $ babeltrace2 query src.ctf.lttng-live sessions \
133 --params='url="net://localhost"'
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135 Example 2. Query the metadata info (includes the decoded plain text) of
136 a CTF trace located on the local file system.
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138 $ babeltrace2 query src.ctf.fs metadata-info \
139 --params='inputs=["/path/to/trace"]'
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141 Example 3. Query the trace infos of a CTF trace located on the local
142 file system.
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144 $ babeltrace2 query src.ctf.fs babeltrace.trace-infos \
145 --params='inputs=["/path/to/trace"]'
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147 Example 4. Query some object from a sink component class without
148 parameters.
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150 $ babeltrace2 query sink.my-plugin.my-sink some-object
151
153 Babeltrace 2 library
154 BABELTRACE_EXEC_ON_ABORT=CMDLINE
155 Execute the command line CMDLINE, as parsed like a UNIX 98 shell,
156 when any part of the Babeltrace 2 project unexpectedly aborts.
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158 The application only aborts when the executed command returns,
159 ignoring its exit status.
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161 This environment variable is ignored when the application has the
162 setuid or the setgid access right flag set.
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164 BABELTRACE_TERM_COLOR=(AUTO | NEVER | ALWAYS)
165 Force the terminal color support for the babeltrace2(1) program and
166 the project’s plugins.
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168 The available values are:
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170 AUTO
171 Only emit terminal color codes when the standard output and
172 error streams are connected to a color-capable terminal.
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174 NEVER
175 Never emit terminal color codes.
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177 ALWAYS
178 Always emit terminal color codes.
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180 BABELTRACE_TERM_COLOR_BRIGHT_MEANS_BOLD=0
181 Set to 0 to emit SGR (see
182 <https://en.wikipedia.org/wiki/ANSI_escape_code>) codes 90 to 97
183 for bright colors instead of bold (SGR code 1) and standard color
184 codes (SGR codes 30 to 37).
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186 BABELTRACE_PLUGIN_PATH=PATHS
187 Set the list of directories, in order, in which dynamic plugins can
188 be found before other directories are considered to PATHS
189 (colon-separated, or semicolon on Windows).
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191 LIBBABELTRACE2_DISABLE_PYTHON_PLUGINS=1
192 Disable the loading of any Babeltrace 2 Python plugin.
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194 LIBBABELTRACE2_INIT_LOG_LEVEL=LVL
195 Force the Babeltrace 2 library’s initial log level to be LVL.
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197 If this environment variable is set, it overrides the log level set
198 by the --log-level option for the Babeltrace 2 library logger.
199
200 The available values for LVL are:
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202 NONE, N
203 Logging is disabled.
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205 FATAL, F
206 Severe errors that lead the execution to abort immediately.
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208 This level should be enabled in production.
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210 ERROR, E
211 Errors that might still allow the execution to continue.
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213 Usually, once one or more errors are reported at this level,
214 the application, plugin, or library won’t perform any more
215 useful task, but it should still exit cleanly.
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217 This level should be enabled in production.
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219 WARN, WARNING, W
220 Unexpected situations which still allow the execution to
221 continue.
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223 This level should be enabled in production.
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225 INFO, I
226 Informational messages that highlight progress or important
227 states of the application, plugins, or library.
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229 This level can be enabled in production.
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231 DEBUG, D
232 Debugging information, with a higher level of details than the
233 TRACE level.
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235 This level should NOT be enabled in production.
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237 TRACE, T
238 Low-level debugging context information.
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240 This level should NOT be enabled in production.
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242 LIBBABELTRACE2_NO_DLCLOSE=1
243 Make the Babeltrace 2 library leave any dynamically loaded modules
244 (plugins and plugin providers) open at exit. This can be useful for
245 debugging purposes.
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247 LIBBABELTRACE2_PLUGIN_PROVIDER_DIR=DIR
248 Set the directory from which the Babeltrace 2 library dynamically
249 loads plugin provider shared objects to DIR.
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251 If this environment variable is set, it overrides the default
252 plugin provider directory.
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254 Babeltrace 2 Python bindings
255 BABELTRACE_PYTHON_BT2_LOG_LEVEL=LVL
256 Force the Babeltrace 2 Python bindings log level to be LVL.
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258 If this environment variable is set, it overrides the log level set
259 by the --log-level option for the Python bindings logger.
260
261 The available values for LVL are:
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263 NONE, N
264 Logging is disabled.
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266 FATAL, F
267 Severe errors that lead the execution to abort immediately.
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269 This level should be enabled in production.
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271 ERROR, E
272 Errors that might still allow the execution to continue.
273
274 Usually, once one or more errors are reported at this level,
275 the application, plugin, or library won’t perform any more
276 useful task, but it should still exit cleanly.
277
278 This level should be enabled in production.
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280 WARN, WARNING, W
281 Unexpected situations which still allow the execution to
282 continue.
283
284 This level should be enabled in production.
285
286 INFO, I
287 Informational messages that highlight progress or important
288 states of the application, plugins, or library.
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290 This level can be enabled in production.
291
292 DEBUG, D
293 Debugging information, with a higher level of details than the
294 TRACE level.
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296 This level should NOT be enabled in production.
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298 TRACE, T
299 Low-level debugging context information.
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301 This level should NOT be enabled in production.
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303 CLI
304 BABELTRACE_CLI_LOG_LEVEL=LVL
305 Force babeltrace2 CLI’s log level to be LVL.
306
307 If this environment variable is set, it overrides the log level set
308 by the --log-level option for the CLI logger.
309
310 The available values for LVL are:
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312 NONE, N
313 Logging is disabled.
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315 FATAL, F
316 Severe errors that lead the execution to abort immediately.
317
318 This level should be enabled in production.
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320 ERROR, E
321 Errors that might still allow the execution to continue.
322
323 Usually, once one or more errors are reported at this level,
324 the application, plugin, or library won’t perform any more
325 useful task, but it should still exit cleanly.
326
327 This level should be enabled in production.
328
329 WARN, WARNING, W
330 Unexpected situations which still allow the execution to
331 continue.
332
333 This level should be enabled in production.
334
335 INFO, I
336 Informational messages that highlight progress or important
337 states of the application, plugins, or library.
338
339 This level can be enabled in production.
340
341 DEBUG, D
342 Debugging information, with a higher level of details than the
343 TRACE level.
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345 This level should NOT be enabled in production.
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347 TRACE, T
348 Low-level debugging context information.
349
350 This level should NOT be enabled in production.
351
352 BABELTRACE_CLI_WARN_COMMAND_NAME_DIRECTORY_CLASH=0
353 Disable the warning message which babeltrace2-convert(1) prints
354 when you convert a trace with a relative path that’s also the name
355 of a babeltrace2 command.
356
357 BABELTRACE_DEBUG=1
358 Legacy variable: equivalent to setting the --log-level option to
359 TRACE.
360
361 BABELTRACE_VERBOSE=1
362 Legacy variable: equivalent to setting the --log-level option to
363 INFO.
364
366 $HOME/.local/lib/babeltrace2/plugins
367 User plugin directory.
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369 /usr/local/lib/babeltrace2/plugins
370 System plugin directory.
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372 /usr/local/lib/babeltrace2/plugin-providers
373 System plugin provider directory.
374
376 0 on success, 1 otherwise.
377
379 If you encounter any issue or usability problem, please report it on
380 the Babeltrace bug tracker (see
381 <https://bugs.lttng.org/projects/babeltrace>).
382
384 The Babeltrace project shares some communication channels with the
385 LTTng project (see <https://lttng.org/>).
386
387 • Babeltrace website (see <https://babeltrace.org/>)
388
389 • Mailing list (see <https://lists.lttng.org>) for support and
390 development: lttng-dev@lists.lttng.org
391
392 • IRC channel (see <irc://irc.oftc.net/lttng>): #lttng on
393 irc.oftc.net
394
395 • Bug tracker (see <https://bugs.lttng.org/projects/babeltrace>)
396
397 • Git repository (see <https://git.efficios.com/?p=babeltrace.git>)
398
399 • GitHub project (see <https://github.com/efficios/babeltrace>)
400
401 • Continuous integration (see
402 <https://ci.lttng.org/view/Babeltrace/>)
403
404 • Code review (see <https://review.lttng.org/q/project:babeltrace>)
405
407 The Babeltrace 2 project is the result of hard work by many regular
408 developers and occasional contributors.
409
410 The current project maintainer is Jérémie Galarneau
411 <mailto:jeremie.galarneau@efficios.com>.
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414 This command is part of the Babeltrace 2 project.
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416 Babeltrace is distributed under the MIT license (see
417 <https://opensource.org/licenses/MIT>).
418
420 babeltrace2-intro(7), babeltrace2(1)
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424Babeltrace 2.0.5 14 September 2019 BABELTRACE2-QUERY(1)