X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=python%2Fguestfs.py;h=a75148e549c24791a30d921ea2654a57a8400fce;hp=4f32ae7276f8bb1ca831a0da102d0719adb8e2bf;hb=d1a1ab972bb22f4c38a21fcc73f81650aaa03b4e;hpb=bfdc03be234d6d95f18450846433bce4f97e184c

diff --git a/python/guestfs.py b/python/guestfs.py
index 4f32ae7..a75148e 100644
--- a/python/guestfs.py
+++ b/python/guestfs.py
@@ -198,6 +198,12 @@ class GuestFS:
         
         This is equivalent to the qemu parameter "-drive
         file=filename".
+        
+        Note that this call checks for the existence of
+        "filename". This stops you from specifying other types
+        of drive which are supported by qemu such as "nbd:" and
+        "http:" URLs. To specify those, use the general
+        "g.config" call instead.
         """
         return libguestfsmod.add_drive (self._o, filename)
 
@@ -207,9 +213,37 @@ class GuestFS:
         
         This is equivalent to the qemu parameter "-cdrom
         filename".
+        
+        Note that this call checks for the existence of
+        "filename". This stops you from specifying other types
+        of drive which are supported by qemu such as "nbd:" and
+        "http:" URLs. To specify those, use the general
+        "g.config" call instead.
         """
         return libguestfsmod.add_cdrom (self._o, filename)
 
+    def add_drive_ro (self, filename):
+        u"""This adds a drive in snapshot mode, making it
+        effectively read-only.
+        
+        Note that writes to the device are allowed, and will be
+        seen for the duration of the guestfs handle, but they
+        are written to a temporary file which is discarded as
+        soon as the guestfs handle is closed. We don't currently
+        have any method to enable changes to be committed,
+        although qemu can support this.
+        
+        This is equivalent to the qemu parameter "-drive
+        file=filename,snapshot=on".
+        
+        Note that this call checks for the existence of
+        "filename". This stops you from specifying other types
+        of drive which are supported by qemu such as "nbd:" and
+        "http:" URLs. To specify those, use the general
+        "g.config" call instead.
+        """
+        return libguestfsmod.add_drive_ro (self._o, filename)
+
     def config (self, qemuparam, qemuvalue):
         u"""This can be used to add arbitrary qemu command line
         parameters of the form "-param value". Actually it's not