mi: add machine interface description to man page

[lttng-tools.git] / doc / man / lttng.1

diff --git a/doc/man/lttng.1 b/doc/man/lttng.1
index cd0aae29466ebfe76b0e04317e544a462a338f0d..80861e905fdcefd9d296931d4f58cab240fd24d2 100644 (file)
--- a/doc/man/lttng.1
+++ b/doc/man/lttng.1
@@ -77,6 +77,26 @@ Simple listing of lttng options.
 .TP
 .BR "\-\-list\-commands"
 Simple listing of lttng commands.
+.TP
+.BR "\-m, \-\-mi TYPE
+Machine interface
+
+TYPE supported: XML
+
+Machine interface (MI) mode converts the traditional pretty printing to a
+machine output syntax. MI mode provides a format change-resistant way to access
+information generated via the lttng command line.
+
+When using MI mode, the data is printed on \fBstdout\fP. Error and warning are
+printed on \fBstderr\fP with the pretty print default format.
+
+If any errors occur during the execution of a command, the return value of the
+command will be different than zero. In this case, lttng does NOT guarantee the
+syntax and data validity of the generated MI output.
+
+For XML output type, a schema definition (XSD) file used for validation can be
+found under src/common/mi_lttng.xsd
+
 .SH "COMMANDS"
 
 .PP
@@ -750,7 +770,9 @@ Load tracing session configuration
 
 If NAME is omitted, all session configurations found in both the user's session
 configuration directory (default: ~/.lttng/sessions/) and the system session
-configuration directory (default: /etc/lttng/sessions/) will be loaded.
+configuration directory (default: /etc/lttng/sessions/) will be loaded. Note
+that the sessions in the user directory are loaded first and then the system
+wide directory are loaded.
 
 .B OPTIONS:
 
@@ -781,6 +803,9 @@ If SESSION is omitted, all session configurations will be saved to individual
 ~/.lttng/sessions/). The default session configuration file naming scheme is
 \fBSESSION.lttng\fP.
 
+For instance, a user in the tracing group saving a session from a root session
+daemon will save it in her/his user directory.
+
 .B OPTIONS:
 
 .TP