From 99c850b2087a6e4802398aae0ba711be6e43d15d Mon Sep 17 00:00:00 2001
Message-Id: <99c850b2087a6e4802398aae0ba711be6e43d15d.1715293620.git.mdw@distorted.org.uk>
From: Mark Wooding <mdw@chiark.greenend.org.uk>
Date: Sun, 13 Jan 2002 13:34:18 +0000
Subject: [PATCH] Describe ancient interface change on immediate failure.
Organization: Straylight/Edgeware

From: mdw <mdw>

---
 man/conn.3 | 35 +++++++++++++++++++++++++++--------
 1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/man/conn.3 b/man/conn.3
index f9dd0d2..3ecc43f 100644
--- a/man/conn.3
+++ b/man/conn.3
@@ -8,10 +8,10 @@ conn \- selector for nonblocking connections
 .nf
 .B "#include <mLib/conn.h>"
 
-.BI "void conn_init(conn *" c ", sel_state *" s ", int " fd ,
-.BI "               struct sockaddr *" dst ", int " dsz ,
-.BI "               void (*" func ")(int " fd ", void *" p ),
-.BI "               void *" p );
+.BI "int conn_init(conn *" c ", sel_state *" s ", int " fd ,
+.BI "              struct sockaddr *" dst ", int " dsz ,
+.BI "              void (*" func ")(int " fd ", void *" p ),
+.BI "              void *" p );
 
 .BI "void conn_kill(conn *" c );
 .fi
@@ -61,15 +61,34 @@ to
 .B conn_init
 as the
 .I p
-argument.  If the connection failed, a file descriptor value of \-1 is
-passed, and the global
-.B errno
-value is set appropriately.
+argument.
 .TP
 .BI "void *" p
 An arbitrary pointer whose value is passed to the handler function when
 the connection finishes.
 .PP
+A few words are in order about
+.BR conn_init 's
+detailed behaviour and return value.  If the it returns \-1, the
+connection attempt has failed immediately (an error code is stored in
+the global variable
+.BR errno ),
+the file descriptor has been
+.IR closed ,
+and the connection function will
+.I not
+be called.  If it returns zero, then there has been no immediate
+failure; the connection function
+.I might
+have been called, if the connection succeeded immediately, but it will
+certainly be called some time, unless the connector is killed (see
+.B conn_kill
+below).  When the connection function is called, it will either be
+passed the file descriptor of the new-connected socket (to indicate
+success) or the value \-1 for failure; in the latter case, an
+appropriate error code is stored in
+.BR errno .
+.PP
 If you want to cancel the connection attempt before it finishes, call
 .B conn_kill
 with the address of the selector.  The file descriptor is closed, and
-- 
[mdw]