Added comments for API functions

README.md

@@ -4,17 +4,21 @@ KUP is comprised of a FreeBSD kernel module, and a userspace library that provid
 The KUP kernel module, exposes an API in the kernel sapce, that a kernel module can use to definea pseudo-device and the max number of channels on that device. Then a userspace process can use the KUP userspace lib to communicate with the kernel-side client.
 
 # Example
-You can take a look at the tests folder to see examples of how to use the kernel module and the usespace library. As a reference here is the KUP kernel API functions (see kupdev/kupdev.h)
+You can take a look at the tests folder to see examples of how to use the kernel module and the usespace library. As a reference here is the KUP kernel API functions (see kuplib/kup.h and kupdev/kupdev.h)
 ```c
+// Create a new KUP device with name /dev/name with a count of chan_cnt
+// channels, each having a size of size pages.
 struct kupdev_softc *
 kupdev_create(const char *name, size_t size, size_t chan_cnt);
 
+// Wait until a userspace process attaches a channel on this KUP device
 int
 kupdev_wait_channel(struct kupdev_softc *sc);
 
 int
 kupdev_unload(struct kupdev_softc* sc);
 
+// Notify the userspace that a new KUP channel is available
 void
 kupdev_notify(struct kupdev_softc *sc);
 
@@ -24,9 +28,11 @@ kupdev_send(struct kupdev_softc *sc, void *data, size_t len, int chan_id);
 void*
 kupdev_receive(struct kupdev_softc *sc, int chan_id);
 
+// Free a receive cahnnel after we are done with the data in it.
 void
 kupdev_unlock_channel(struct kupdev_softc* sc, int chan_id);
 
+// Pass the turn on channel chan_of of KUP device sc to the userspace process
 void
 kupdev_pass(struct kupdev_softc* sc, int chan_id);
 ```
@@ -37,6 +43,7 @@ int kernproxy_errno;
 
 void* kernproxy_open(char const *name);
 
+// Attach to a specific channel of the KUP device represented by handle
 void* kernproxy_channel(void* handle, size_t chan_id, size_t size);
 
 void* kernproxy_receive(void *handle, int flags);