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'\" t
.\" Title: lttng-add-trigger
.\" Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\" Date: 14 June 2021
.\" Manual: LTTng Manual
.\" Source: LTTng 2.13.15
.\" Language: English
.\"
.TH "LTTNG\-ADD\-TRIGGER" "1" "14 June 2021" "LTTng 2\&.13\&.15" "LTTng Manual"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
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.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
lttng-add-trigger \- Add an LTTng trigger
.SH "SYNOPSIS"
.sp
.nf
\fBlttng\fR [\fIGENERAL OPTIONS\fR] \fBadd\-trigger\fR [\fB--name\fR=\fINAME\fR] [\fB--owner-uid\fR=\fIUID\fR]
\fB--condition\fR=\fICONDTYPE\fR [\fICONDARGS\fR]
\fB--action\fR=\fIACTTYPE\fR [\fIACTARGS\fR] [\fB--action\fR=\fIACTTYPE\fR [\fIACTARGS\fR]]\&...
.fi
.SH "DESCRIPTION"
.sp
The \fBlttng add-trigger\fR command creates and adds an LTTng \fItrigger\fR to the connected session daemon (see \fBlttng-sessiond\fR(8))\&.
.sp
See \fBlttng-concepts\fR(7) to learn more about LTTng triggers\&.
.sp
By default, the \fBadd-trigger\fR command automatically assigns a name, unique for a given session daemon and Unix user, to the added trigger\&. Assign a custom name with the \fB--name\fR\&.
.sp
The \fBadd-trigger\fR command adds a trigger for your Unix user\&. If your Unix user is \fBroot\fR, you may add the trigger as another user with the \fB--owner-uid\fR option\&.
.sp
Specify the condition of the trigger to add with a condition specifier and its actions with one or more action specifiers\&. The order of the action specifiers is significant: LTTng attempts to execute the actions of a firing trigger in this order\&.
.sp
See the \(lqEXAMPLES\(rq section below for usage examples\&.
.sp
List the triggers of your Unix user, or of all users if your Unix user is \fBroot\fR, with the \fBlttng-list-triggers\fR(1) command\&.
.sp
Remove a trigger with the \fBlttng-remove-trigger\fR(1) command\&.
.SS "Condition specifier"
.sp
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--condition\fR=\fICONDTYPE\fR [\fICONDARGS\fR]
.fi
.if n \{\
.RE
.\}
.sp
A condition specifier is the \fB--condition\fR option, which specifies the type of condition \fICONDTYPE\fR, followed, depending on \fICONDTYPE\fR, with zero or more arguments \fICONDARGS\fR\&.
.sp
The available condition types are:
.PP
\fBevent-rule-matches\fR
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--condition\fR=\fBevent\-rule\-matches\fR [\fB--capture\fR=\fICDESCR\fR]\&... \fIERSPEC\fR
\ \&
.fi
.if n \{\
.RE
.\}
An
\fBevent-rule-matches\fR
condition is considered satisfied when the event rule specified with
\fIERSPEC\fR
matches an event\&.
.sp
See
\fBlttng-event-rule\fR(7)
to learn how to specify an event rule (\fIERSPEC\fR
part)\&.
.sp
Capture event record and context fields with one or more
\fB--capture\fR
options (see the \(lqCapture descriptor\(rq section below to learn more)\&. When an
\fBevent-rule-matches\fR
condition with capture descriptors is satisfied, the captured field values are available in the evaluation object of the condition using the liblttng\-ctl C\ \&API\&.
.if n \{\
.sp
.\}
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBImportant\fR
.ps -1
.br
.RS 4
Make sure to
\fBsingle\-quote\fR
\fICDESCR\fR
when you run the
\fBadd-trigger\fR
command from a shell, as capture descriptors can include characters having a special meaning for most shells\&.
.sp .5v
.RE
.RE
.SS "Capture descriptor"
.sp
A capture descriptor is a textual expression which describes how to read an event record or context field\&.
.sp
The argument of a \fB--capture\fR option, when using an \(lqevent rule matches\(rq condition specifier (\fBevent-rule-matches\fR), is a capture descriptor\&.
.sp
A capture descriptor expression is one of:
.PP
\fINAME\fR
.RS 4
An event record field named
\fINAME\fR\&.
.sp
The supported event record field types are:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Integer
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Enumeration (integral value)
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Floating point number
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Static array of integers
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Dynamic array (\(lqsequence\(rq) of integers
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Text string
.RE
.sp
Examples:
\fBmy_field\fR,
\fBtarget_cpu\fR,
\fBip\fR\&.
.RE
.PP
\fB$ctx.\fR\fINAME\fR
.RS 4
A statically\-known context field named
\fINAME\fR\&.
.sp
List the available statically\-known context field names with
\fBlttng-add-context\fR(1)\&.
.sp
Examples:
\fB$ctx.prio\fR,
\fB$ctx.preemptible\fR,
\fB$ctx.perf:cpu:stalled-cycles-frontend\fR\&.
.RE
.PP
\fB$app.\fR\fIPROVIDER\fR\fB.\fR\fINAME\fR
.RS 4
An application\-specific context field named
\fINAME\fR
from the provider
\fIPROVIDER\fR\&.
.sp
See
\fBlttng-add-context\fR(1)
to learn more about application\-specific context fields\&.
.sp
Example:
\fB$app.server:cur_user\fR\&.
.RE
.PP
\fIEXPR\fR\fB[\fR\fIINDEX\fR\fB]\fR
.RS 4
The element at index
\fIINDEX\fR
of the array field (static or dynamic) identified by the expression
\fIEXPR\fR\&.
.sp
\fIINDEX\fR
must be a constant, positive integral value\&.
.sp
Examples:
\fBip[3]\fR,
\fBuser_ids[15]\fR\&.
.RE
.sp
If, when an event rule matches, a given capture descriptor doesn\(cqt identify an existing event or context field, then the captured value is reported as being unavailable\&. This applies to:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
A nonexistent event record field name\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
A nonexistent statically\-known context field name\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
A nonexistent application\-specific context field name\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
An out\-of\-bounds array field index\&.
.RE
.SS "Action specifier"
.sp
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fIACTTYPE\fR [\fIACTARGS\fR]
.fi
.if n \{\
.RE
.\}
.sp
An action specifier is the \fB--action\fR option, which specifies the type of action \fIACTTYPE\fR, followed, depending on \fIACTTYPE\fR, with zero or more arguments \fIACTARGS\fR\&.
.sp
The available action types are:
.PP
Notify
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fBnotify\fR [\fB--rate-policy\fR=\fIPOLICY\fR]
\ \&
.fi
.if n \{\
.RE
.\}
Sends a notification through the notification mechanism of the session daemon (see
\fBlttng-sessiond\fR(8))\&.
.sp
The session daemon sends details about the condition evaluation along with the notification\&.
.sp
As of LTTng\ \&2\&.13\&.15, you can write a C/C++ program to receive LTTng notifications (see the liblttng\-ctl C\ \&headers)\&.
.sp
See below for the
\fB--rate-policy\fR
option\&.
.RE
.PP
Start a recording session
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fBstart\-session\fR \fISESSION\fR [\fB--rate-policy\fR=\fIPOLICY\fR]
\ \&
.fi
.if n \{\
.RE
.\}
Starts the recording session named
\fISESSION\fR
like
\fBlttng-start\fR(1)
would\&.
.sp
If no recording session has the name
\fISESSION\fR
when LTTng is ready to execute the action, LTTng does nothing\&.
.sp
See below for the
\fB--rate-policy\fR
option\&.
.RE
.PP
Stop a recording session
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fBstop\-session\fR \fISESSION\fR [\fB--rate-policy\fR=\fIPOLICY\fR]
\ \&
.fi
.if n \{\
.RE
.\}
Stops the recording session named
\fISESSION\fR
like
\fBlttng-stop\fR(1)
would\&.
.sp
If no recording session has the name
\fISESSION\fR
when LTTng is ready to execute the action, LTTng does nothing\&.
.sp
See below for the
\fB--rate-policy\fR
option\&.
.RE
.PP
Rotate a recording session
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fBrotate\-session\fR \fISESSION\fR [\fB--rate-policy\fR=\fIPOLICY\fR]
\ \&
.fi
.if n \{\
.RE
.\}
Archives the current trace chunk of the recording session named
\fISESSION\fR
like
\fBlttng-rotate\fR(1)
would\&.
.sp
If no recording session has the name
\fISESSION\fR
when LTTng is ready to execute the action, LTTng does nothing\&.
.sp
See below for the
\fB--rate-policy\fR
option\&.
.RE
.PP
Take a recording session snapshot
.RS 4
Synopsis:
.sp
.if n \{\
.RS 4
.\}
.nf
\fB--action\fR=\fBsnapshot\-session\fR \fISESSION\fR [\fB--rate-policy\fR=\fIPOLICY\fR]
\ \&
.fi
.if n \{\
.RE
.\}
Takes a snapshot of the recording session named
\fISESSION\fR
like
\fBlttng-snapshot\fR(1)
would\&.
.sp
When the condition of the trigger is satisfied, the recording session named
\fISESSION\fR, if any, must be a snapshot\-mode recording session (see
\fBlttng-create\fR(1))\&.
.sp
If no recording session has the name
\fISESSION\fR
when LTTng is ready to execute the action, LTTng does nothing\&.
.sp
See below for the
\fB--rate-policy\fR
option\&.
.RE
.sp
Common action options (as of LTTng\ \&2\&.13\&.15):
.PP
\fB--rate-policy\fR=\fIPOLICY\fR
.RS 4
Set the rate policy of the action to
\fIPOLICY\fR
instead of
\fBevery:1\fR
(always execute)\&.
.sp
A trigger which \(lqfires\(rq (its condition is satisfied) leads to an execution request for each of its actions, in order\&. An execution request of a given action\ \&\fIA\fR
first increments the execution request count\ \&\fIC\fR
of\ \&\fIA\fR\&. An execution request can then become an actual execution when\ \&\fIC\fR
satisfies the rate policy of\ \&\fIA\fR\&.
.sp
\fIPOLICY\fR
is one of:
.PP
\fBonce-after:\fR\fICOUNT\fR
.RS 4
Only execute\ \&\fIA\fR
when\ \&\fIC\fR
is equal to
\fICOUNT\fR\&.
.sp
In other words, execute\ \&\fIA\fR
a single time after
\fICOUNT\fR
execution requests\&.
.RE
.PP
\fBevery:\fR\fICOUNT\fR
.RS 4
Only execute\ \&\fIA\fR
when\ \&\fIC\fR
is a multiple of
\fICOUNT\fR\&.
.sp
In other words, execute\ \&\fIA\fR
every
\fICOUNT\fR
execution requests\&.
.RE
.sp
\fICOUNT\fR
must be an integer greater than\ \&0\&.
.sp
As of LTTng\ \&2\&.13\&.15, you can use this option with any action type, but new action types in the future may not support it\&.
.RE
.SH "OPTIONS"
.SS "Identification"
.PP
\fB--name\fR=\fINAME\fR
.RS 4
Set the unique name of the trigger to add to
\fINAME\fR
instead of the
\fBadd-trigger\fR
command automatically assigning one\&.
.RE
.PP
\fB--owner-uid\fR=\fIUID\fR
.RS 4
Add the trigger as the Unix user having the user ID
\fIUID\fR\&.
.sp
You may only use this option if your Unix user is
\fBroot\fR\&.
.RE
.SS "Specifier"
.PP
\fB--condition\fR=\fICONDTYPE\fR
.RS 4
Introductory option for a condition specifier of type
\fICONDTYPE\fR\&.
.sp
See the \(lqCondition specifier\(rq section above to learn more\&.
.RE
.PP
\fB--action\fR=\fIACTTYPE\fR
.RS 4
Introductory option for an action specifier of type
\fIACTTYPE\fR\&.
.sp
See the \(lqAction specifier\(rq section above to learn more\&.
.RE
.SS "Program information"
.PP
\fB-h\fR, \fB--help\fR
.RS 4
Show help\&.
.sp
This option attempts to launch
\fB/usr/bin/man\fR
to view this manual page\&. Override the manual pager path with the
\fBLTTNG_MAN_BIN_PATH\fR
environment variable\&.
.RE
.PP
\fB--list-options\fR
.RS 4
List available command options and quit\&.
.RE
.SH "EXIT STATUS"
.PP
\fB0\fR
.RS 4
Success
.RE
.PP
\fB1\fR
.RS 4
Command error
.RE
.PP
\fB2\fR
.RS 4
Undefined command
.RE
.PP
\fB3\fR
.RS 4
Fatal error
.RE
.PP
\fB4\fR
.RS 4
Command warning (something went wrong during the command)
.RE
.SH "ENVIRONMENT"
.PP
\fBLTTNG_ABORT_ON_ERROR\fR
.RS 4
Set to
\fB1\fR
to abort the process after the first error is encountered\&.
.RE
.PP
\fBLTTNG_HOME\fR
.RS 4
Path to the LTTng home directory\&.
.sp
Defaults to
\fB$HOME\fR\&.
.sp
Useful when the Unix user running the commands has a non\-writable home directory\&.
.RE
.PP
\fBLTTNG_MAN_BIN_PATH\fR
.RS 4
Absolute path to the manual pager to use to read the LTTng command\-line help (with
\fBlttng-help\fR(1)
or with the
\fB--help\fR
option) instead of
\fB/usr/bin/man\fR\&.
.RE
.PP
\fBLTTNG_SESSION_CONFIG_XSD_PATH\fR
.RS 4
Path to the directory containing the
\fBsession.xsd\fR
recording session configuration XML schema\&.
.RE
.PP
\fBLTTNG_SESSIOND_PATH\fR
.RS 4
Absolute path to the LTTng session daemon binary (see
\fBlttng-sessiond\fR(8)) to spawn from the
\fBlttng-create\fR(1)
command\&.
.sp
The
\fB--sessiond-path\fR
general option overrides this environment variable\&.
.RE
.SH "FILES"
.PP
\fB$LTTNG_HOME/.lttngrc\fR
.RS 4
Unix user\(cqs LTTng runtime configuration\&.
.sp
This is where LTTng stores the name of the Unix user\(cqs current recording session between executions of
\fBlttng\fR(1)\&.
\fBlttng-create\fR(1)
and
\fBlttng-set-session\fR(1)
set the current recording session\&.
.RE
.PP
\fB$LTTNG_HOME/lttng-traces\fR
.RS 4
Default output directory of LTTng traces in local and snapshot modes\&.
.sp
Override this path with the
\fB--output\fR
option of the
\fBlttng-create\fR(1)
command\&.
.RE
.PP
\fB$LTTNG_HOME/.lttng\fR
.RS 4
Unix user\(cqs LTTng runtime and configuration directory\&.
.RE
.PP
\fB$LTTNG_HOME/.lttng/sessions\fR
.RS 4
Default directory containing the Unix user\(cqs saved recording session configurations (see
\fBlttng-save\fR(1)
and
\fBlttng-load\fR(1))\&.
.RE
.PP
\fB/usr/local/etc/lttng/sessions\fR
.RS 4
Directory containing the system\-wide saved recording session configurations (see
\fBlttng-save\fR(1)
and
\fBlttng-load\fR(1))\&.
.RE
.if n \{\
.sp
.\}
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBNote\fR
.ps -1
.br
.RS 4
.sp
\fB$LTTNG_HOME\fR defaults to the value of the \fBHOME\fR environment variable\&.
.sp .5v
.RE
.SH "EXAMPLES"
.PP
\fBExample\ \&1.\ \&Add an \(lqevent rule matches\(rq trigger of which the action is to send a notification\&.\fR
.RS 4
.sp
The \fBevent-rule-matches\fR trigger condition below specifies an event rule which matches any Linux system call entry event with a name starting with \fBexec\fR\&.
.sp
.if n \{\
.RS 4
.\}
.nf
$ lttng add\-trigger \-\-condition=event\-rule\-matches \e
\-\-type=syscall:entry \e
\-\-name=\*(Aqexec*\*(Aq \-\-action=notify
.fi
.if n \{\
.RE
.\}
.RE
.PP
\fBExample\ \&2.\ \&Add an \(lqevent rule matches\(rq trigger of which the action is to stop a recording session and then rotate it\&.\fR
.RS 4
.sp
The \fBevent-rule-matches\fR trigger condition below specifies an event rule which matches any user space tracepoint event with a name starting with \fBmy_app:\fR and with a log level at least as severe as a warning\&.
.sp
The order of the \fB--action\fR options below is significant\&.
.sp
.if n \{\
.RS 4
.\}
.nf
$ lttng add\-trigger \-\-condition=event\-rule\-matches \e
\-\-type=user \-\-name=\*(Aqmy_app:*\*(Aq \e
\-\-log\-level=TRACE_WARNING\&.\&. \e
\-\-action=stop\-session my\-session \e
\-\-action=rotate\-session my\-session
.fi
.if n \{\
.RE
.\}
.sp
See \fBlttng-concepts\fR(7) to learn more about recording sessions and rotations\&.
.RE
.PP
\fBExample\ \&3.\ \&Add an \(lqevent rule matches\(rq trigger with a specific name\&.\fR
.RS 4
.sp
The \fBevent-rule-matches\fR trigger condition below specifies an event rule which matches events which LTTng creates from the \fBmy-logger\fR Python logger\&.
.sp
The added trigger is named \fBmy-trigger\fR, a unique name for your Unix user\&.
.sp
See the \fB--name\fR option\&.
.sp
.if n \{\
.RS 4
.\}
.nf
$ lttng add\-trigger \-\-name=my\-trigger \e
\-\-condition=event\-rule\-matches \e
\-\-type=python \-\-name=my\-logger \e
\-\-action=snapshot\-session my\-session
.fi
.if n \{\
.RE
.\}
.RE
.PP
\fBExample\ \&4.\ \&Add an \(lqevent rule matches\(rq trigger as another Unix user\&.\fR
.RS 4
.sp
The command line below adds a trigger as the \fBmireille\fR Unix user\&.
.sp
Your Unix user must be \fBroot\fR to use the \fB--owner-uid\fR option\&.
.sp
The condition of the trigger specifies an event rule which matches LTTng kernel tracepoint events with a name which starts with \fBsched\fR\&.
.sp
.if n \{\
.RS 4
.\}
.nf
# lttng add\-trigger \-\-owner\-uid=$(id \-\-user mireille) \e
\-\-condition=event\-rule\-matches \e
\-\-type=kernel \-\-name=\*(Aqsched*\*(Aq \e
\-\-action=notify
.fi
.if n \{\
.RE
.\}
.RE
.PP
\fBExample\ \&5.\ \&Add an \(lqevent rule matches\(rq trigger with a notification action to be executed every 10\ \×\&.\fR
.RS 4
.sp
The \fBevent-rule-matches\fR trigger condition below specifies an event rule which matches all user space tracepoint events\&.
.sp
See the \fB--rate-policy\fR option above\&.
.sp
.if n \{\
.RS 4
.\}
.nf
$ lttng add\-trigger \-\-condition=event\-rule\-matches \e
\-\-type=user \-\-action=notify \e
\-\-rate\-policy=every:10
.fi
.if n \{\
.RE
.\}
.RE
.PP
\fBExample\ \&6.\ \&Add an \(lqevent rule matches\(rq trigger with a recording session starting action to be executed a single time after 40\ \×\&.\fR
.RS 4
.sp
The \fBevent-rule-matches\fR trigger condition below specifies an event rule which matches any Linux system call event (entry and exit) of which the \fBfd\fR event record field is less than\ \&3\&.
.sp
See the \fB--rate-policy\fR option above\&.
.sp
.if n \{\
.RS 4
.\}
.nf
$ lttng add\-trigger \-\-condition=event\-rule\-matches \e
\-\-type=syscall \-\-filter=\*(Aqfd < 3\*(Aq \e
\-\-action=start\-session my\-session \e
\-\-rate\-policy=once\-after:40
.fi
.if n \{\
.RE
.\}
.RE
.SH "RESOURCES"
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
LTTng project website <https://lttng.org>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
LTTng documentation <https://lttng.org/docs>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
LTTng bug tracker <https://bugs.lttng.org>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Git repositories <https://git.lttng.org>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
GitHub organization <https://github.com/lttng>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Continuous integration <https://ci.lttng.org/>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Mailing list <https://lists.lttng.org/>
for support and development:
\fBlttng-dev@lists.lttng.org\fR
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
IRC channel <irc://irc.oftc.net/lttng>:
\fB#lttng\fR
on
\fBirc.oftc.net\fR
.RE
.SH "COPYRIGHT"
.sp
This program is part of the LTTng\-tools project\&.
.sp
LTTng\-tools is distributed under the GNU General Public License version\ \&2 <http://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html>\&. See the \fBLICENSE\fR <https://github.com/lttng/lttng-tools/blob/master/LICENSE> file for details\&.
.SH "THANKS"
.sp
Special thanks to Michel Dagenais and the DORSAL laboratory <http://www.dorsal.polymtl.ca/> at \('Ecole Polytechnique de Montr\('eal for the LTTng journey\&.
.sp
Also thanks to the Ericsson teams working on tracing which helped us greatly with detailed bug reports and unusual test cases\&.
.SH "SEE ALSO"
.sp
\fBlttng\fR(1), \fBlttng-list-triggers\fR(1), \fBlttng-remove-trigger\fR(1), \fBlttng-concepts\fR(7)
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