It depends of your communication settings (Console > clients > policies > communication settings).
If you are in Push mode, the connection is always in place and the Manager immediately push the new policies to the clients so a command is not implemented because it is not necessary.
If you are in Pull mode, the connection is open by the clients at every heartbeat to check for new policies and contents. In this communication mode if you issue a command from manager to clients it will be executed during the next heartbeat that includes the checking for new policies therefore even in this case a specific command is useless.
If in a client you don't want to wait the next heartbeat you can right-click on the yellow shield and press "update policies...".

Cheers,

Wow Sandeep  - good call.
However, I find here that I cannot stop the SMC service - I suspect it is a setting or policy I have. You can't stop it command line or in the services list. The option isn't there.
I love that smc -updateconfig option and will have to save that.
For weeks I thought you were a Symantec employee! LOL - that's how good you are.

That's because it's not set at the system level.

You have two ways of doing it in a batch file.(or cmd)

start smc -stop
start smc -start

or using the full path name for the smc.exe.
like c:\program files\symantec\symantec endpoint protection\smc.exe -stop