ceph.in: print more detailed error message for 'tell' command

* we do not allow user specify a certain daemon when starting an
  interactive session. the existing error message could lead to
  some confusion. so put more details in it.

Fixes: #11101
Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/src/ceph.in b/src/ceph.in
index 3e70d8e0ad033303d766fd9db5fbd9d57a0b9283..7ee4e4a92ab86d9f41dd41c46d5fffce66ca5178 100755 (executable)
--- a/src/ceph.in
+++ b/src/ceph.in
@@ -772,7 +772,9 @@ def main():
             childargs = injectargs
         if not len(childargs):
             print >> sys.stderr, \
-                'Cannot use \'tell\' with interactive mode'
+                'Cannot use \'tell\' with interactive mode.', \
+                'For an interactive shell,', \
+                'please start "{0}" without non-option arguments.'.format(sys.argv[0])
             return errno.EINVAL
 
     # fetch JSON sigs from command