doxygen: Improve documentation of struct receiver.

The documentation still referred to the former gengetopt related
->conf pointer and also had some language and punctuation issues. The
new text should fix this, and is more to the point.

diff --git a/recv.h b/recv.h
index f1e2fc4563735a67f149bdc69d1bbf7f526497d6..6fb70b9a70897e65232732a71194f666236b5a1c 100644 (file)
--- a/recv.h
+++ b/recv.h
@@ -52,11 +52,9 @@ struct receiver {
        /**
         * Open one instance of the receiver.
         *
-        * This should allocate the output buffer of \a rn. and may also
-        * perform any other work necessary for retrieving the stream according
-        * to the configuration stored in the \a conf member of \a rn which is
-        * guaranteed to point to valid configuration data (as previously
-        * obtained from the config parser).
+        * This should allocate the output buffer of the given receiver node
+        * and prepare it for retrieving the audio stream according to the
+        * configuration stored in rn->lpr.
         *
         * \sa struct \ref receiver_node.
         */
@@ -73,31 +71,32 @@ struct receiver {
        /**
         * Add file descriptors to fd_sets and compute timeout for select(2).
         *
-        * The pre_select function gets called from the driving application
-        * before entering its select loop. The receiver may use this hook to
-        * add any file descriptors to the sets of file descriptors given by \a
-        * s.
+        * If this is not NULL, the function is called in each iteration of the
+        * scheduler's select loop. The receiver may define it to add file
+        * descriptors to the file descriptor sets given by s. Those will be
+        * monitored in the subsequent call to select(2). The function may also
+        * lower the timeout value of s to make select(2) return earlier if no
+        * file descriptors are ready for I/O.
         *
         * \sa select(2), \ref time.c, struct \ref sched.
         */
        void (*pre_select)(struct sched *s, void *context);
        /**
-        * Evaluate the result from select().
+        * Evaluate the result from select(2).
         *
-        * This hook gets called after the call to select(). It should check
-        * all file descriptors which were added to any of the fd sets during
-        * the previous call to pre_select. According to the result, it may
-        * then use any non-blocking I/O to establish a connection or to
-        * receive the audio data.
+        * This is called after the call to select(2). It should check all file
+        * descriptors which were added to any of the fd sets in the previous
+        * call to ->pre_select() and perform (non-blocking) I/O operations on
+        * those fds which are ready for I/O, for example in order to establish
+        * a connection or to receive a part of the audio stream.
         *
         * \sa select(2), struct \ref receiver.
         */
        int (*post_select)(struct sched *s, void *context);
-
        /**
         * Answer a buffer tree query.
         *
-        * This optional function pointer is used for inter node communications
+        * This optional function pointer allows for inter node communication
         * of the buffer tree nodes. See \ref btr_command_handler for details.
         */
        btr_command_handler execute;