'\" t
.\"     Title: lttng-load
.\"    Author: [FIXME: author] [see http://www.docbook.org/tdg5/en/html/author]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 28 November 2016
.\"    Manual: LTTng Manual
.\"    Source: LTTng 2.12.3
.\"  Language: English
.\"
.TH "LTTNG\-LOAD" "1" "28 November 2016" "LTTng 2\&.12\&.3" "LTTng Manual"
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.SH "NAME"
lttng-load \- Load LTTng tracing session configurations
.SH "SYNOPSIS"
.sp
.nf
\fBlttng\fR [\fIGENERAL OPTIONS\fR] \fBload\fR [\fB--force\fR] [\fB--input-path\fR=\fIPATH\fR]
      [\fB--override-url\fR=\fIURL\fR] [\fISESSION\fR [\fB--override-name\fR=\fINAME\fR]]
.fi
.SH "DESCRIPTION"
.sp
The \fBlttng load\fR command loads the configurations of one or more tracing sessions from files\&.
.sp
The \fBlttng load\fR command is used in conjunction with the \fBlttng-save\fR(1) command to save and restore the complete configurations of tracing sessions\&. This includes the enabled channels and event rules, the context added to channels, the tracing activity, and more\&.
.sp
Once one or more tracing session configurations are loaded, they appear exactly as they were saved from the user\(cqs point of view\&.
.sp
The following directories are searched, non\-recursively, in this order for configuration files:
.sp
.RS 4
.ie n \{\
\h'-04' 1.\h'+01'\c
.\}
.el \{\
.sp -1
.IP "  1." 4.2
.\}
\fB$LTTNG_HOME/.lttng/sessions\fR
(\fB$LTTNG_HOME\fR
defaults to
\fB$HOME\fR)
.RE
.sp
.RS 4
.ie n \{\
\h'-04' 2.\h'+01'\c
.\}
.el \{\
.sp -1
.IP "  2." 4.2
.\}
\fB/etc/lttng/sessions\fR
.RE
.sp
The input path can be overridden with the \fB--input-path\fR option\&. When this option is specified, the default directories are NOT searched for configuration files\&. When it\(cqs not specified, \fIboth\fR default directories are searched for configuration files\&.
.sp
If the input path is a \fBdirectory\fR, then:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
If
\fISESSION\fR
is specified, the tracing session configuration named
\fISESSION\fR
is searched for in all the files of this directory and loaded if found\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
If
\fISESSION\fR
is not specified, the
\fB--all\fR
option is implicit: all the tracing session configurations found in all the files in this directory are loaded\&.
.RE
.sp
If the input path is a \fBfile\fR, then:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
If
\fISESSION\fR
is specified, the tracing session configuration named
\fISESSION\fR
is searched for in this file and loaded if found\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
If
\fISESSION\fR
is not specified, the
\fB--all\fR
option is implicit: all the tracing session configurations found in this file are loaded\&.
.RE
.sp
Aspects of the loaded configurations can be overridden at load time using the \fB--override-url\fR and \fB--override-name\fR options\&.
.sp
By default, existing tracing sessions are not overwritten when loading: the command fails\&. The \fB--force\fR option can be used to allow this\&.
.SH "OPTIONS"
.sp
General options are described in \fBlttng\fR(1)\&.
.PP
\fB-a\fR, \fB--all\fR
.RS 4
Load all tracing session configurations (default)\&.
.RE
.PP
\fB-f\fR, \fB--force\fR
.RS 4
Overwrite existing tracing sessions when loading\&.
.RE
.PP
\fB-i\fR \fIPATH\fR, \fB--input-path\fR=\fIPATH\fR
.RS 4
Load tracing session configurations from
\fIPATH\fR, either a directory or a file, instead of loading them from the default search directories\&.
.RE
.PP
\fB--override-name\fR=\fINAME\fR
.RS 4
Override the name of the loaded tracing session configuration,
\fISESSION\fR, with
\fINAME\fR\&.
.sp
You must specify a tracing session name to load (\fISESSION\fR) and NOT use the
\fB--all\fR
option when using this option\&.
.RE
.PP
\fB--override-url\fR=\fIURL\fR
.RS 4
Override the URL of the loaded tracing session configurations with
\fIURL\fR\&.
.sp
This is the equivalent of the
\fB--set-url\fR
option of
\fBlttng-create\fR(1)\&. The validity of the URL override depends on the type of tracing session configurations to load\&. This option applies to
\fIall\fR
the loaded tracing session configurations\&.
.RE
.SS "Program information"
.PP
\fB-h\fR, \fB--help\fR
.RS 4
Show command help\&.
.sp
This option, like
\fBlttng-help\fR(1), attempts to launch
\fB/usr/bin/man\fR
to view the command\(cqs man page\&. The path to the man pager can be overridden by the
\fBLTTNG_MAN_BIN_PATH\fR
environment variable\&.
.RE
.PP
\fB--list-options\fR
.RS 4
List available command options\&.
.RE
.SH "ENVIRONMENT VARIABLES"
.PP
\fBLTTNG_ABORT_ON_ERROR\fR
.RS 4
Set to 1 to abort the process after the first error is encountered\&.
.RE
.PP
\fBLTTNG_HOME\fR
.RS 4
Overrides the
\fB$HOME\fR
environment variable\&. Useful when the user running the commands has a non\-writable home directory\&.
.RE
.PP
\fBLTTNG_MAN_BIN_PATH\fR
.RS 4
Absolute path to the man pager to use for viewing help information about LTTng commands (using
\fBlttng-help\fR(1)
or
\fBlttng COMMAND --help\fR)\&.
.RE
.PP
\fBLTTNG_SESSION_CONFIG_XSD_PATH\fR
.RS 4
Path in which the
\fBsession.xsd\fR
session configuration XML schema may be found\&.
.RE
.PP
\fBLTTNG_SESSIOND_PATH\fR
.RS 4
Full session daemon binary path\&.
.sp
The
\fB--sessiond-path\fR
option has precedence over this environment variable\&.
.RE
.sp
Note that the \fBlttng-create\fR(1) command can spawn an LTTng session daemon automatically if none is running\&. See \fBlttng-sessiond\fR(8) for the environment variables influencing the execution of the session daemon\&.
.SH "FILES"
.PP
\fB$LTTNG_HOME/.lttngrc\fR
.RS 4
User LTTng runtime configuration\&.
.sp
This is where the per\-user current tracing session is stored between executions of
\fBlttng\fR(1)\&. The current tracing session can be set with
\fBlttng-set-session\fR(1)\&. See
\fBlttng-create\fR(1)
for more information about tracing sessions\&.
.RE
.PP
\fB$LTTNG_HOME/lttng-traces\fR
.RS 4
Default output directory of LTTng traces\&. This can be overridden with the
\fB--output\fR
option of the
\fBlttng-create\fR(1)
command\&.
.RE
.PP
\fB$LTTNG_HOME/.lttng\fR
.RS 4
User LTTng runtime and configuration directory\&.
.RE
.PP
\fB$LTTNG_HOME/.lttng/sessions\fR
.RS 4
Default location of saved user tracing sessions (see
\fBlttng-save\fR(1)
and
\fBlttng-load\fR(1))\&.
.RE
.PP
\fB/etc/lttng/sessions\fR
.RS 4
System\-wide location of saved tracing sessions (see
\fBlttng-save\fR(1)
and
\fBlttng-load\fR(1))\&.
.RE
.if n \{\
.sp
.\}
.RS 4
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBNote\fR
.ps -1
.br
.sp
\fB$LTTNG_HOME\fR defaults to \fB$HOME\fR when not explicitly set\&.
.sp .5v
.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 "BUGS"
.sp
If you encounter any issue or usability problem, please report it on the LTTng bug tracker <https://bugs.lttng.org/projects/lttng-tools>\&.
.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
.\}
Git repositories <http://git.lttng.org>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
GitHub organization <http://github.com/lttng>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Continuous integration <http://ci.lttng.org/>
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
Mailing list <http://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 "COPYRIGHTS"
.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-save\fR(1), \fBlttng\fR(1)