This patch introduces a feature whereby rrdcached will disallow updates

[rrdtool.git] / doc / rrdxport.pod

diff --git a/doc/rrdxport.pod b/doc/rrdxport.pod
index ca0e3aa..d7e6bb3 100644 (file)
--- a/doc/rrdxport.pod
+++ b/doc/rrdxport.pod
@@ -4,20 +4,21 @@ rrdxport - Export data in XML format based on data from one or several RRD
 
 =head1 SYNOPSIS
 
-B<rrdtool> B<xport> 
-S<[B<-s>|B<--start> I<seconds>]> 
+B<rrdtool> B<xport>
+S<[B<-s>|B<--start> I<seconds>]>
 S<[B<-e>|B<--end> I<seconds>]>
 S<[B<-m>|B<--maxrows> I<rows>]>
 S<[B<--step> I<value>]>
+S<[B<--daemon> I<address>]>
 S<[B<DEF:>I<vname>B<=>I<rrd>B<:>I<ds-name>B<:>I<CF>]>
 S<[B<CDEF:>I<vname>B<=>I<rpn-expression>]>
 S<[B<XPORT>B<:>I<vname>[B<:>I<legend>]]>
 
 =head1 DESCRIPTION
 
-The B<xport> functions main purpose is to write XML formatted
+The B<xport> function's main purpose is to write an XML formatted
 representation of the data stored in one or several B<RRD>s. It
-can also extract numerical reports. 
+can also extract numerical reports.
 
 If no I<XPORT> statements are found, there will be no output.
 
@@ -48,6 +49,21 @@ for details.
 
 See L<rrdgraph> documentation.
 
+=item B<--daemon> I<address>
+
+Address of the L<rrdcached> daemon. If specified, a C<flush> command is sent
+to the server before reading the RRD files. This allows B<rrdtool> to return
+fresh data even if the daemon is configured to cache values for a long time.
+For a list of accepted formats, see the B<-l> option in the L<rrdcached> manual.
+
+  rrdtool xport --daemon unix:/var/run/rrdcached.sock ...
+
+=item B<--enumds>
+
+The generated xml should contain the data values in enumerated tags.
+
+ <v0>val</v0><v1>val</v1>
+
 =item B<DEF:>I<vname>B<=>I<rrd>B<:>I<ds-name>B<:>I<CF>
 
 See I<rrdgraph> documentation.
@@ -65,9 +81,9 @@ referenced by I<vname> are printed. Optionally add a legend.
 
 =head1 Output format
 
-The output is enclosed in a B<xport> element and contains two
+The output is enclosed in an B<xport> element and contains two
 blocks. The first block is enclosed by a B<meta> element and
-contains some meta data. The second block is enclosed by a 
+contains some meta data. The second block is enclosed by a
 B<data> element and contains the data rows.
 
 Let's assume that the I<xport> command looks like this:
@@ -80,9 +96,9 @@ Let's assume that the I<xport> command looks like this:
           XPORT:xx:"out bytes" \
           XPORT:aa:"in and out bits"
 
-The resulting meta data section (the values will depend on the
+The resulting meta data section is (the values will depend on the
 RRD characteristics):
- 
+
   <meta>
     <start>1020611700</start>
     <step>300</step>
@@ -94,8 +110,8 @@ RRD characteristics):
       <entry>in and out bits</entry>
     </legend>
   </meta>
-  
-The resulting data section:
+
+The resulting data section is:
 
   <data>
     <row><t>1020611700</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
@@ -131,8 +147,22 @@ The resulting data section:
           XPORT:out2:"if2 out bytes" \
          XPORT:sum:"output sum"
 
+=head1 ENVIRONMENT VARIABLES
+
+The following environment variables may be used to change the behavior of
+C<rrdtoolE<nbsp>xport>:
+
+=over 4
+
+=item B<RRDCACHED_ADDRESS>
+
+If this environment variable is set it will have the same effect as specifying
+the C<--daemon> option on the command line. If both are present, the command
+line argument takes precedence.
+
+=back
 
 =head1 AUTHOR
 
-Tobias Oetiker E<lt>oetiker@ee.ethz.chE<gt>
+Tobias Oetiker E<lt>tobi@oetiker.chE<gt>