lttng-help(1)

1LTTNG-HELP(1)                    LTTng Manual                    LTTNG-HELP(1)
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NAME

6       lttng-help - Display help information about an LTTng command
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SYNOPSIS

9       lttng [GENERAL OPTIONS] help [COMMAND]
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DESCRIPTION

12       The lttng help command displays help information about an LTTng
13       command.
14
15       This command is the equivalent of:
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17           $ lttng COMMAND --help
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19       where COMMAND is the name of the command about which to get help. If
20       COMMAND is omitted, lttng help shows general help about the lttng(1)
21       command.
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23       The lttng help command attempts to launch /usr/bin/man to view the
24       command’s man page. The path to the man pager can be overridden by the
25       LTTNG_MAN_BIN_PATH environment variable.
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OPTIONS

28       General options are described in lttng(1).
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30   Program information
31       -h, --help
32           Show command help.
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34           This option, like lttng-help(1), attempts to launch /usr/bin/man to
35           view the command’s man page. The path to the man pager can be
36           overridden by the LTTNG_MAN_BIN_PATH environment variable.
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38       --list-options
39           List available command options.
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ENVIRONMENT VARIABLES

42       LTTNG_ABORT_ON_ERROR
43           Set to 1 to abort the process after the first error is encountered.
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45       LTTNG_HOME
46           Overrides the $HOME environment variable. Useful when the user
47           running the commands has a non-writable home directory.
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49       LTTNG_MAN_BIN_PATH
50           Absolute path to the man pager to use for viewing help information
51           about LTTng commands (using lttng-help(1) or lttng COMMAND --help).
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53       LTTNG_SESSION_CONFIG_XSD_PATH
54           Path in which the session.xsd session configuration XML schema may
55           be found.
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57       LTTNG_SESSIOND_PATH
58           Full session daemon binary path.
59
60           The --sessiond-path option has precedence over this environment
61           variable.
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63       Note that the lttng-create(1) command can spawn an LTTng session daemon
64       automatically if none is running. See lttng-sessiond(8) for the
65       environment variables influencing the execution of the session daemon.
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FILES

68       $LTTNG_HOME/.lttngrc
69           User LTTng runtime configuration.
70
71           This is where the per-user current tracing session is stored
72           between executions of lttng(1). The current tracing session can be
73           set with lttng-set-session(1). See lttng-create(1) for more
74           information about tracing sessions.
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76       $LTTNG_HOME/lttng-traces
77           Default output directory of LTTng traces. This can be overridden
78           with the --output option of the lttng-create(1) command.
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80       $LTTNG_HOME/.lttng
81           User LTTng runtime and configuration directory.
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83       $LTTNG_HOME/.lttng/sessions
84           Default location of saved user tracing sessions (see lttng-save(1)
85           and lttng-load(1)).
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87       /usr/local/etc/lttng/sessions
88           System-wide location of saved tracing sessions (see lttng-save(1)
89           and lttng-load(1)).
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91           Note
92           $LTTNG_HOME defaults to $HOME when not explicitly set.
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EXIT STATUS

95       0
96           Success
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98       1
99           Command error
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101       2
102           Undefined command
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104       3
105           Fatal error
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107       4
108           Command warning (something went wrong during the command)
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BUGS

111       If you encounter any issue or usability problem, please report it on
112       the LTTng bug tracker <https://bugs.lttng.org/projects/lttng-tools>.
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RESOURCES

115       ·   LTTng project website <http://lttng.org>
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117       ·   LTTng documentation <http://lttng.org/docs>
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119       ·   Git repositories <http://git.lttng.org>
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121       ·   GitHub organization <http://github.com/lttng>
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123       ·   Continuous integration <http://ci.lttng.org/>
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125       ·   Mailing list <http://lists.lttng.org> for support and development:
126           lttng-dev@lists.lttng.org
127
128       ·   IRC channel <irc://irc.oftc.net/lttng>: #lttng on irc.oftc.net
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COPYRIGHTS

131       This program is part of the LTTng-tools project.
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133       LTTng-tools is distributed under the GNU General Public License version
134       2 <http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html>. See the
135       LICENSE <https://github.com/lttng/lttng-tools/blob/master/LICENSE> file
136       for details.
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THANKS

139       Special thanks to Michel Dagenais and the DORSAL laboratory
140       <http://www.dorsal.polymtl.ca/> at École Polytechnique de Montréal for
141       the LTTng journey.
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143       Also thanks to the Ericsson teams working on tracing which helped us
144       greatly with detailed bug reports and unusual test cases.
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AUTHORS

147       LTTng-tools was originally written by Mathieu Desnoyers, Julien
148       Desfossez, and David Goulet. More people have since contributed to it.
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150       LTTng-tools is currently maintained by Jérémie Galarneau
151       <mailto:jeremie.galarneau@efficios.com>.
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