Make version notes more accurate

Ref2_eventbase.txt

@@ -305,7 +305,7 @@ By default, all new events associated with this base will be initialized
 with priority equal to n_priorities / 2.
 
 The event_base_priority_init function is defined in <event2/event.h>. It has
-been available since before Libevent 1.0.
+been available since Libevent 1.0.
 
 
 Reinitializing an event_base after fork()
@@ -367,7 +367,6 @@ This function worked like event_base_new(), and set the current base
 to the allocated base. There was no other way to change the
 current base.
 
-
 Some of the event_base functions in this section had variants that
 operated on the current base. These functions behaved as the current
 functions, except that they took no base argument.
@@ -379,6 +378,3 @@ functions, except that they took no base argument.
 | event_base_get_method() | event_get_method()
 |======================================================================
 
-// FIXME Undocumented:
-// event_base_make_notifiable()
-

Ref3_eventloop.txt

@@ -75,7 +75,7 @@ flags set. Thus, it keeps running until there are no more registered events
 or until event_base_loopbreak() or event_base_loopexit() is called.
 
 These functions are defined in <event2/event.h>. They have existed since
-before Libevent 1.0.
+Libevent 1.0.
 
 Stopping the loop
 ~~~~~~~~~~~~~~~~~

Ref4_event.txt

@@ -196,7 +196,8 @@ improving the clarity of your code.
  event_pending((ev), (what), (tv_out))
 --------
 
-These macros have been present since before Libevent 1.0.
+These macros have been present since Libevent 0.6, except for evtimer_new(),
+which first appeared in Libevent 2.0.1-alpha.
 
 Constructing signal events
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -498,7 +499,7 @@ When you do not set the priority for an event, the default is the
 number of queues in the event base, divided by 2.
 
 This function is declared in <event2/event.h>. It has existed since
-before Libevent 1.0.
+Libevent 1.0.
 
 Inspecting event status
 ~~~~~~~~~~~~~~~~~~~~~~~

Ref6_bufferevent.txt

@@ -340,7 +340,7 @@ If the BEV_OPT_CLOSE_ON_FREE flag was set, and this bufferevent has a
 socket or underlying bufferevent associated with it as its transport,
 that transport is closed when you free the bufferevent.
 
-This function was introduced before Libevent 1.0.
+This function was introduced in Libevent 0.8.
 
 Manipulating callbacks, watermarks, and enabled operations
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -402,7 +402,7 @@ reading.
 You can call bufferevent_get_enabled() to see which events are currently
 enabled on the bufferevent.
 
-These functions were introduced before Libevent 1.0, except for
+These functions were introduced in Libevent 0.8, except for
 bufferevent_get_enabled(), which was introduced in version 2.0.3-alpha.
 
 .Interface
@@ -542,7 +542,7 @@ end of the output buffer. Calling bufferevent_write_buffer() removes
 the entire contents of 'buf' and puts them at the end of the output
 buffer. Both return 0 if successful, or -1 if an error occurred.
 
-These functions have existed since before Libevent 1.0.
+These functions have existed since Libevent 0.8.
 
 .Interface
 [code,C]
@@ -562,7 +562,7 @@ drains the entire contents of the input buffer and places them into
 Note that with bufferevent_read(), the memory chunk at 'data' must
 actually have enough space to hold 'size' bytes of data.
 
-The bufferevent_read() function has existed since before Libevent 1.0;
+The bufferevent_read() function has existed since Libevent 0.8;
 bufferevent_read_buffer() was introduced in Libevent 2.0.1-alpha.
 
 .Example
@@ -675,7 +675,7 @@ As of Libevent 2.0.2-alpha, only socket-based bufferevents support
 timeouts. More bufferevent types should support timeouts in the
 future.
 
-This functions has existed since Libevent 2.0.1-alpha
+This functions has existed since Libevent 2.0.1-alpha.
 
 Initiating a flush on a bufferevent
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -710,7 +710,7 @@ priorities.
 This function returns 0 on success, and -1 on failure. It works on
 socket-based bufferevents only.
 
-This function was introduced before Libevent 1.0.
+This function was introduced in Libevent 1.0.
 
 .Interface
 [code,C]
@@ -723,7 +723,7 @@ These functions set or return the file descriptor for a fd-based
 event. Only socket-based bufferevents support setfd(). Both return
 -1 on failure; setfd() returns 0 on success.
 
-The bufferevent_setfd() function was introduced before Libevent 1.4.4;
+The bufferevent_setfd() function was introduced in Libevent 1.4.4;
 the bufferevent_getfd() function was introduced in Libevent 2.0.2-alpha.
 
 .Interface
@@ -770,9 +770,10 @@ Libevent 2.0:
 The old functions were defined in event.h, not in event2/bufferevent.h.
 
 If you still need access to the internals of the common parts of the
-bufferevent struct, include event2/bufferevent_struct.h. The macros
-and names in this section are available if you include
-event2/bufferevent_compat.h.
+bufferevent struct, you can include event2/bufferevent_struct.h. We
+recommend against it: the contents of struct bufferevent WILL change between
+versions of Libevent. The macros and names in this section are available if
+you include event2/bufferevent_compat.h.
 
 The interface to set up a bufferevent differed in older versions:
 
@@ -795,5 +796,5 @@ void bufferevent_settimeout(struct bufferevent *bufev,
 --------
 
 Finally, note that the underlying evbuffer implementation for Libevent
-versions before 2.0 makes using bufferevents for high-performance apps
-kind of questionable.
+versions before 2.0 was pretty inefficient, to the point where using
+bufferevents for high-performance apps was kind of questionable.

Ref7_evbuffer.txt

@@ -30,7 +30,7 @@ These functions should be relatively clear: evbuffer_new() allocates
 and returns a new empty evbuffer, and evbuffer_free() deletes one and
 all of its contents.
 
-These functions have existed since before Libevent 1.0.
+These functions have existed since Libevent 0.8.
 
 Evbuffers and Thread-safety
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -135,9 +135,9 @@ evbuffer_add(buf, "Hello world 2.0.1", 17);
 evbuffer_add_printf(buf, "Hello %s %d.%d.%d", "world", 2, 0, 1);
 --------
 
-The evbuffer_add(), evbuffer_add_printf(), and evbuffer_expand() functions
-were introduced before Libevent 1.0; and evbuffer_add_printf() first
-appeared in Libevent 1.1.
+The evbuffer_add() and evbuffer_add_printf() functions were introduced in
+Libevent 0.8; evbuffer_expand() was in Libevent 0.9, and
+evbuffer_add_printf() first appeared in Libevent 1.1.
 
 Moving data from one evbuffer to another
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -161,7 +161,7 @@ from 'src' to the end of 'dst', copying as little as possible. If
 there are fewer than 'datlen' bytes to move, it moves all the bytes.
 It returns the number of bytes moved.
 
-We introduced evbuffer_add_buffer() before Libevent 1.0;
+We introduced evbuffer_add_buffer() in Libevent 0.8;
 evbuffer_remove_buffer() was new in Libevent 2.0.1-alpha.
 
 Adding data to the front of an evbuffer
@@ -271,7 +271,8 @@ The evbuffer_drain() function behaves as evbuffer_remove(), except
 that it does not copy the data: it just removes it from the front of
 the buffer. It returns 0 on success and -1 on failure.
 
-These functions have existed since before Libevent 1.0.
+Libevent 0.8 introduced evbuffer_drain(); evbuffer_remove() appeared in
+Libevent 0.9.
 
 Line-oriented input
 ~~~~~~~~~~~~~~~~~~~

Ref8_listener.txt

@@ -9,7 +9,8 @@ The evconnlistener mechanism gives you a way to listen for and accept
 incoming TCP connections.
 
 All the functions and types in this section are declared in
-event2/listener.h. They first appeared in Libevent 2.0.2-alpha.
+event2/listener.h. They first appeared in Libevent 2.0.2-alpha, unless
+otherwise noted.
 
 Creating or freeing an evconnlistener
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -124,6 +125,8 @@ struct event_base *evconnlistener_get_base(struct evconnlistener *lev);
 These functions return a listener's associated socket and event_base
 respectively.
 
+The evconnlistener_get_fd() function first appeared in Libevent 2.0.3-alpha.
+
 Example code: an echo server.
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~