In every "service call" command, you need to enter:
- the service you want to call, in this case it is "isms";
- the "function" you want to call, in this case it is "5" (more about that later);
- the function parameters.
There's two types of possible parameters: Strings and Integers. Before entering an Integer parameter you need to specify its type using i32.
Same thing for a String parameter, but instead you need to write s16.
Most of the "service call" commands have no documentation, or very little.
For the ISms you can look here: http://www.androidjavadoc.com/1.0_r1_src/constant-values.html
to get a list of the possible functions and their number code. Hit ctrl-f and enter ISms for quick access.
The "5" function for the ISms service is the sendMultipartText function from the ISms interface of the Android API. Here is the doc about this function. And here is the implementation class from the API.
So, service call isms 5 s16 "PhoneNumber" i32 0 i32 0 s16 "BodyText", equals:
Call the sendMultipartText function from the ISms service with the
String parameter "PhoneNumber", the Integer parameter 0, the Integer
parameter 0 and the String parameter "BodyText".
To answer your question, I am pretty sure there's no way to know if the sms are being sent or not from the command line... But maybe if you dig a little deeper than I did in the API you'll find a way.