--- name: "babeltrace2-query" section: "1" platform: "linux" package: "babeltrace2" version: "2.1.1-1" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/babeltrace2-query" --- # babeltrace2-query(1) Query an object from a Babeltrace 2 component class ## NAME babeltrace2-query - Query an object from a Babeltrace 2 component class ## SYNOPSIS ``` babeltrace2 [GENERAL OPTIONS] query [--params=PARAMS] COMP-CLS-TYPE.PLUGIN-NAME.COMP-CLS-NAME OBJECT ``` ## DESCRIPTION The **query** command queries the object named *OBJECT* from the component class named *COMP-CLS-NAME* of the type *COMP-CLS-TYPE* found in the Babeltrace 2 plugin named *PLUGIN-NAME* and prints the results. See [**babeltrace2-intro**(7)](/babeltrace2-intro/7.md) to learn more about the Babeltrace 2 project and its core concepts. The available values for *COMP-CLS-TYPE* are: **source**, **src** Source component class. **filter**, **flt** Filter component class. **sink** Sink component class. The exact object names and the parameters that a given component class expects are described in its own documentation. [**babeltrace2-help**(1)](/babeltrace2-help/1.md) can generally provide this information. You can use the **--params** option to pass parameters to the query operation of the component class. The output of the **query** command can look like YAML (see \), but it’s not guaranteed to be YAML-compliant. See “EXAMPLES” for usage examples. ## OPTIONS ### General You can use those options before the command name. See [**babeltrace2**(1)](/babeltrace2/1.md) for more details. - **-d**, **--debug** Legacy option: this is equivalent to **--log-level**=**TRACE**. - **-l** *LVL*, **--log-level**=*LVL* Set the log level of all known Babeltrace 2 loggers to *LVL*. - **--omit-home-plugin-path** Don’t search for plugins in **$HOME/.local/lib/babeltrace2/plugins**. - **--omit-system-plugin-path** Don’t search for plugins in **/usr/lib/babeltrace2/plugins**. - **--plugin-path**=*PATH*\[:*PATH*\]... Add *PATH* to the list of paths in which plugins can be found. - **-v**, **--verbose** Legacy option: this is equivalent to **--log-level**=**INFO**. ### Query parameters - **-p** *PARAMS*, **--params**=*PARAMS* Set the query parameters to *PARAMS*. The format of *PARAMS* is a comma-separated list of *NAME*=*VALUE* assignments: ``` NAME=VALUE[,NAME=VALUE]... ``` *NAME* Parameter name (C identifier plus the **:**, **.**, and **-** characters). *VALUE* One of: • **null**, **nul**, **NULL**: null value. • **true**, **TRUE**, **yes**, **YES**: true boolean value. • **false**, **FALSE**, **no**, **NO**: false boolean value. • Binary (**0b** prefix), octal (**0** prefix), decimal, or hexadecimal (**0x** prefix) unsigned (with **+** prefix) or signed 64-bit integer. • Double precision floating point number (scientific notation is accepted). • Unquoted string with no special characters, and not matching any of the null and boolean value symbols above. • Double-quoted string (accepts escape characters). • Array, formatted as an opening **\[**, a comma-separated list of *VALUE*, and a closing **\]**. • Map, formatted as an opening **{**, a comma-separated list of *NAME*=*VALUE* assignments, and a closing **}**. You may put whitespaces around the individual **=** (assignment), **,** (separator), **\[** (array beginning), **\]** (array end), **{** (map beginning), and **}** (map end) characters. Example: ``` --params='many=null, fresh=yes, condition=false, squirrel=-782329, play=+23, observe=3.14, simple=beef, needs-quotes="some string", escape.chars-are:allowed="a \" quote", things=[1, "hello", 2.71828], frog={slow=2, bath=[bike, 23], blind=NO}' ``` **Important**\ Like in the example above, make sure to single-quote the whole argument when you run this command from a shell, as it can contain many special characters. ### Command information - **-h**, **--help** Show the command help and quit. ## EXAMPLES **Example 1. Query the available tracing sessions of a local LTTng relay daemon.** ``` $ babeltrace2 query src.ctf.lttng-live sessions \ --params='url="net://localhost"' ``` **Example 2. Query the metadata info (includes the decoded plain text) of a CTF trace located on the local file system.** ``` $ babeltrace2 query src.ctf.fs metadata-info \ --params='inputs=["/path/to/trace"]' ``` **Example 3. Query the trace infos of a CTF trace located on the local file system.** ``` $ babeltrace2 query src.ctf.fs babeltrace.trace-infos \ --params='inputs=["/path/to/trace"]' ``` **Example 4. Query some object from a sink component class without parameters.** ``` $ babeltrace2 query sink.my-plugin.my-sink some-object ``` ## ENVIRONMENT VARIABLES ### Babeltrace 2 library **BABELTRACE\_EXEC\_ON\_ABORT**=*CMDLINE* Execute the command line *CMDLINE*, as parsed like a UNIX 98 shell, when any part of the Babeltrace 2 project unexpectedly aborts. The application only aborts when the executed command returns, ignoring its exit status. This environment variable is ignored when the application has the **setuid** or the **setgid** access right flag set. **BABELTRACE\_TERM\_COLOR**=(**AUTO** \| **NEVER** \| **ALWAYS**) Force the terminal color support for the [**babeltrace2**(1)](/babeltrace2/1.md) program and the project plugins. The available values are: **AUTO** Only emit terminal color codes when the standard output and error streams are connected to a color-capable terminal. **NEVER** Never emit terminal color codes. **ALWAYS** Always emit terminal color codes. **BABELTRACE\_TERM\_COLOR\_BRIGHT\_MEANS\_BOLD**=**0** Set to **0** to emit SGR (see \) codes 90 to 97 for bright colors instead of bold (SGR code 1) and standard color codes (SGR codes 30 to 37). **BABELTRACE\_PLUGIN\_PATH**=*PATHS* Set the list of directories, in order, in which dynamic plugins can be found before other directories are considered to *PATHS* (colon-separated, or semicolon on Windows). **LIBBABELTRACE2\_DISABLE\_PYTHON\_PLUGINS**=**1** Disable the loading of any Babeltrace 2 Python plugin. **LIBBABELTRACE2\_INIT\_LOG\_LEVEL**=*LVL* Force the initial log level of the Babeltrace 2 library to be *LVL*. If this environment variable is set, then it overrides the log level set by the **--log-level** option for the Babeltrace 2 library logger. The available values for *LVL* are: **NONE**, **N** Logging is disabled. **FATAL**, **F** Severe errors that lead the execution to abort immediately. This level should be enabled in production. **ERROR**, **E** Errors that might still allow the execution to continue. Usually, once one or more errors are reported at this level, the application, plugin, or library won’t perform any more useful task, but it should still exit cleanly. This level should be enabled in production. **WARN**, **WARNING**, **W** Unexpected situations which still allow the execution to continue. This level should be enabled in production. **INFO**, **I** Informational messages that highlight progress or important states of the application, plugins, or library. This level can be enabled in production. **DEBUG**, **D** Debugging information, with a higher level of details than the **TRACE** level. This level should NOT be enabled in production. **TRACE**, **T** Low-level debugging context information. This level should NOT be enabled in production. **LIBBABELTRACE2\_NO\_DLCLOSE**=**1** Make the Babeltrace 2 library leave any dynamically loaded modules (plugins and plugin providers) open at exit. This can be useful for debugging purposes. **LIBBABELTRACE2\_PLUGIN\_PROVIDER\_DIR**=*DIR* Set the directory from which the Babeltrace 2 library dynamically loads plugin provider shared objects to *DIR*. If this environment variable is set, then it overrides the default plugin provider directory. ### Babeltrace 2 Python bindings **BABELTRACE\_PYTHON\_BT2\_LOG\_LEVEL**=*LVL* Force the Babeltrace 2 Python bindings log level to be *LVL*. If this environment variable is set, then it overrides the log level set by the **--log-level** option for the Python bindings logger. The available values for *LVL* are: **NONE**, **N** Logging is disabled. **FATAL**, **F** Severe errors that lead the execution to abort immediately. This level should be enabled in production. **ERROR**, **E** Errors that might still allow the execution to continue. Usually, once one or more errors are reported at this level, the application, plugin, or library won’t perform any more useful task, but it should still exit cleanly. This level should be enabled in production. **WARN**, **WARNING**, **W** Unexpected situations which still allow the execution to continue. This level should be enabled in production. **INFO**, **I** Informational messages that highlight progress or important states of the application, plugins, or library. This level can be enabled in production. **DEBUG**, **D** Debugging information, with a higher level of details than the **TRACE** level. This level should NOT be enabled in production. **TRACE**, **T** Low-level debugging context information. This level should NOT be enabled in production. ### CLI **BABELTRACE\_CLI\_LOG\_LEVEL**=*LVL* Force the log level of the log level **babeltrace2** CLI to be *LVL*. If this environment variable is set, then it overrides the log level set by the **--log-level** option for the CLI logger. The available values for *LVL* are: **NONE**, **N** Logging is disabled. **FATAL**, **F** Severe errors that lead the execution to abort immediately. This level should be enabled in production. **ERROR**, **E** Errors that might still allow the execution to continue. Usually, once one or more errors are reported at this level, the application, plugin, or library won’t perform any more useful task, but it should still exit cleanly. This level should be enabled in production. **WARN**, **WARNING**, **W** Unexpected situations which still allow the execution to continue. This level should be enabled in production. **INFO**, **I** Informational messages that highlight progress or important states of the application, plugins, or library. This level can be enabled in production. **DEBUG**, **D** Debugging information, with a higher level of details than the **TRACE** level. This level should NOT be enabled in production. **TRACE**, **T** Low-level debugging context information. This level should NOT be enabled in production. **BABELTRACE\_CLI\_WARN\_COMMAND\_NAME\_DIRECTORY\_CLASH**=**0** Disable the warning message which [**babeltrace2-convert**(1)](/babeltrace2-convert/1.md) prints when you convert a trace with a relative path that’s also the name of a **babeltrace2** command. **BABELTRACE\_DEBUG**=**1** Legacy variable: equivalent to setting the **--log-level** option to **TRACE**. **BABELTRACE\_VERBOSE**=**1** Legacy variable: equivalent to setting the **--log-level** option to **INFO**. ## FILES **$HOME/.local/lib/babeltrace2/plugins** User plugin directory. **/usr/lib/babeltrace2/plugins** System plugin directory. **/usr/lib/babeltrace2/plugin-providers** System plugin provider directory. ## EXIT STATUS **0** on success, **1** otherwise. ## BUGS If you encounter any issue or usability problem, please report it on the Babeltrace bug tracker (see \). ## RESOURCES The Babeltrace project shares some communication channels with the LTTng project (see \). • Babeltrace website (see \) • Mailing list (see \) for support and development: **lttng-dev@lists.lttng.org** • IRC channel (see \): **#lttng** on **irc.oftc.net** • Bug tracker (see \) • Git repository (see \) • GitHub project (see \) • Continuous integration (see \) • Code review (see \) ## AUTHORS The Babeltrace 2 project is the result of hard work by many regular developers and occasional contributors. The current project maintainer is Jérémie Galarneau \. ## COPYRIGHT This command is part of the Babeltrace 2 project. Babeltrace is distributed under the MIT license (see \). ## SEE ALSO [**babeltrace2-intro**(7)](/babeltrace2-intro/7.md), [**babeltrace2**(1)](/babeltrace2/1.md)