man: Document DPKG_RUNNING_VERSION environment variable

debian/changelog

@@ -37,6 +37,8 @@ dpkg (1.15.4) UNRELEASED; urgency=low
     architecture the package got built for.
   * Document DPKG_MAINTSCRIPT_PACKAGE maintainer script environment variable
     in dpkg man page.
+  * Document DPKG_RUNNING_VERSION maintainer script environment variable
+    in dpkg man page.
   * Change po4a usage to not create unwated changes depending if doing out or
     in-tree builds.
   * Use po4a “--previous” support when updating the man pages.

man/dpkg.1

@@ -1,4 +1,4 @@
-.TH dpkg 1 "2009-08-20" "Debian Project" "dpkg suite"
+.TH dpkg 1 "2009-09-06" "Debian Project" "dpkg suite"
 .SH NAME
 dpkg \- package manager for Debian
 .
@@ -624,6 +624,10 @@ The program \fBdpkg\fP will execute when starting a new shell.
 Sets the number of columns \fBdpkg\fP should use when displaying formatted
 text. Currently only used by \-l.
 .TP
+.B DPKG_RUNNING_VERSION
+Defined by \fBdpkg\fP on the maintainer script environment to the
+version of the currently running \fBdpkg\fP instance.
+.TP
 .B DPKG_MAINTSCRIPT_PACKAGE
 Defined by \fBdpkg\fP on the maintainer script environment to the
 package name being handled.