X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=perl%2Flib%2FSys%2FGuestfs.pm;h=a13c4411d7b5ed9651ee6706a31a0027a389d794;hp=9501a83f9b729b756037b940c5aa3485008a5767;hb=8c3b820c2b687345448e3d74a7101b07ff32688e;hpb=ac286b26df1aabceca26dac66c325a3676ace4cc

diff --git a/perl/lib/Sys/Guestfs.pm b/perl/lib/Sys/Guestfs.pm
index 9501a83..a13c441 100644
--- a/perl/lib/Sys/Guestfs.pm
+++ b/perl/lib/Sys/Guestfs.pm
@@ -452,6 +452,17 @@ There is no comprehensive help for this command.  You have
 to look at the file C<daemon/debug.c> in the libguestfs source
 to find out what you can do.
 
+=item $kmsgs = $h->dmesg ();
+
+This returns the kernel messages (C<dmesg> output) from
+the guest kernel.  This is sometimes useful for extended
+debugging of problems.
+
+Another way to get the same information is to enable
+verbose messages with C<$h-E<gt>set_verbose> or by setting
+the environment variable C<LIBGUESTFS_DEBUG=1> before
+running the program.
+
 =item $h->download ($remotefilename, $filename);
 
 Download file C<remotefilename> and save it as C<filename>
@@ -461,6 +472,18 @@ C<filename> can also be a named pipe.
 
 See also C<$h-E<gt>upload>, C<$h-E<gt>cat>.
 
+=item $h->drop_caches ($whattodrop);
+
+This instructs the guest kernel to drop its page cache,
+and/or dentries and inode caches.  The parameter C<whattodrop>
+tells the kernel what precisely to drop, see
+L<http://linux-mm.org/Drop_Caches>
+
+Setting C<whattodrop> to 3 should drop everything.
+
+This automatically calls L<sync(2)> before the operation,
+so that the maximum guest memory is freed.
+
 =item $existsflag = $h->exists ($path);
 
 This returns C<true> if and only if there is a file, directory
@@ -749,6 +772,13 @@ Some internal mounts are not shown.
 This moves a file from C<src> to C<dest> where C<dest> is
 either a destination filename or destination directory.
 
+=item $h->ping_daemon ();
+
+This is a test probe into the guestfs daemon running inside
+the qemu subprocess.  Calling this function checks that the
+daemon responds to the ping message, without affecting the daemon
+or attached block device(s) in any other way.
+
 =item $h->pvcreate ($device);
 
 This creates an LVM physical volume on the named C<device>,