Pass my system(ls) command to my another client to run

i wish to know how to pass the command like system(ls),system(mkdir) etc to my client.

in my server side i have the send(sd,(?),(?),0);

what to put in the (?) area in order to pass the command mentioned to my client to run.

I understand my client side need to have the
recv(mysock,buf,strlen(buf),0);---is that correct?

what is the way and any advise on this?

case: to ask client enter an char input and server process it and send teh desired command back to the client and perform the desired task in client's side.

thanks

Read these documents

>>recv(mysock,buf,strlen(buf),0);

for send() this would be correct.

In recv() using strlen(buf) and an empty buf will result in no data being read (as you have told recv() the buffer size is zero).
char buf[128];

buf[0]='\0';
lstrlen(buf)=0;
sizeof(buf)=128;

Use sizeof(buf) in this case.