adding some argument descriptions to API.md
# The Demeter Demikernel Syscall API
-This document provide a more detailed explanation of the Demikernel API
+This document provide a more detailed explanation of the Demikernel
+API. All syscalls return 0 if successful and an error code
+otherwise. Each description documents the other incoming and outgoing
+arguments.
#### Calls in `include/dmtr/libos.h`
* `int dmtr_init(int argc, char *argv[]);`
+ * `argc`: in : number of commandline arguments, passed on to the libOS
+ * `argv`: in : values of commandline arguments, passed on to the libOS
> Initialize libOS state. Set up devices, allocate data structures and
> general initialization tasks.
* `int dmtr_queue(int *qd_out);`
+ * `qd_out`: out : queue descriptor for newly allocated queue if
+ successful; otherwise invalid
> Allocate an in-memory demeter queue. Returns a queue descriptor that
> references a FIFO queue (i.e., popping an element from the queue
@@ -17,6 +24,7 @@ This document provide a more detailed explanation of the Demikernel API
* `int dmtr_socket(int *qd_out, int domain, int type, int protocol);`
+
> Allocate demeter queue associated with a socket. Returns queue
> descriptor.
