babeltrace2-help man page

babeltrace2-help — Get help for a Babeltrace 2 plugin or component class

Synopsis

Get help for a Babeltrace 2 plugin:

babeltrace2 [GENERAL OPTIONS] help PLUGIN-NAME

Get help for a Babeltrace 2 component class:

babeltrace2 [GENERAL OPTIONS] help
            COMP-CLS-TYPE.PLUGIN-NAME.COMP-CLS-NAME

Description

The help command prints the details and help text of either the Babeltrace 2 plugin named PLUGIN-NAME or the specific component class of type COMP-CLS-TYPE named COMP-CLS-NAME found in the plugin named PLUGIN-NAME.

See babeltrace2-intro(7) 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.

See “Examples” for usage examples.

Options

General

You can use those options before the command name.

See babeltrace2(1) 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

Do not search for plugins in $HOME/.local/lib/babeltrace2/plugins.

--omit-system-plugin-path

Do not search for plugins in /usr/local/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.

Command information

-h, --help

Show the command’s help and quit.

Examples

Example 1. Get help for a plugin and all its component classes.

$ babeltrace2 help ctf

Example 2. Get help for a specific plugin’s source component class.

$ babeltrace2 help source.ctf.fs

Example 3. Get help for a specific plugin’s sink component class.

$ babeltrace2 help sink.text.pretty

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) program and the project’s 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 <https://en.wikipedia.org/wiki/ANSI_escape_code>) 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 Babeltrace 2 library’s initial log level to be LVL.

If this environment variable is set, 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, 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, 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 babeltrace2 CLI’s log level to be LVL.

If this environment variable is set, 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) 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/local/lib/babeltrace2/plugins

System plugin directory.

/usr/local/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 <https://bugs.lttng.org/projects/babeltrace>).

Resources

The Babeltrace project shares some communication channels with the LTTng project (see <https://lttng.org/>).

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 <mailto:jeremie.galarneau@efficios.com>.

See Also

babeltrace2-intro(7), babeltrace2(1), babeltrace2-list-plugins(1)

Referenced By

babeltrace2(1), babeltrace2-list-plugins(1), babeltrace2-query(1).

14 September 2019 Babeltrace 2.0.1 Babeltrace 2 manual