updated README.md

README.md

@@ -81,6 +81,8 @@ the bash associative array will hold the following contents
 | text            | may contain special symbols            |
 | callback        | callback_data, empty if there is none  |
 
+if you sourced the viewer, you can view these contents with `view_content curmsg` where `curmsg` is the name of the bash associative array populated by getmsg_content
+
 ### sending messages
 use the `sendmsg` function to send messages and print the result to `sentmsgs.txt`