Created attachment 13257 [details]
rpcclient has built-in timeout (10sec) in source3/rpc_client/cli_pipe.c.
#define RPCCLI_DEFAULT_TIMEOUT 10000 /* 10 seconds. */
This default can be changed by the timeout keyword. For example:
rpcclient localhost -c 'timeout 20000; enumprinters'
It doesn't seem to be documented in the manpages. Here is a patch adding it to the man.