fixes #303 Flesh out compatible API docs

1 files changed, 57 insertions, 0 deletions

diff --git a/docs/man/nn_device.3compat.adoc b/docs/man/nn_device.3compat.adoc
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+++ b/docs/man/nn_device.3compat.adoc
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+= nn_device(3compat)
+//
+// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
+// Copyright 2018 Capitar IT Group BV <info@capitar.com>
+//
+// This document is supplied under the terms of the MIT License, a
+// copy of which should be located in the distribution where this
+// file was obtained (LICENSE.txt).  A copy of the license may also be
+// found online at https://opensource.org/licenses/MIT.
+//
+
+== NAME
+
+nn_device - create forwarding device (compatible API)
+
+== SYNOPSIS
+
+[source,c]
+----
+#include <nanomsg/nn.h>
+
+int nn_device(int sock1, int sock2);
+----
+
+== DESCRIPTION
+
+The `nn_device()` function is used to create a forwarder, where messages
+received on one of the two sockets _sock1_ and _sock2_ are forwarded to
+the other.
+
+NOTE: This function is provided for API
+<<nng_compat.3compat#,compatibility>> with legacy _libnanomsg_.
+Consider using the relevant <<libnng.3#,modern API>> instead.
+
+The two sockets must be compatible, and must be <<nng.7#raw_mode,raw mode>>
+sockets.
+More detail about devices and how they can be used is available in the
+new style <<nng_device.3#,nng_device()>> documentation.
+
+== RETURN VALUES
+
+This function blocks forever, and will return -1 only when
+one of the sockets is closed or an error occurs.
+
+== ERRORS
+
+[horizonal]
+`EBADF`:: One of the two sockets is invalid or not open, or has
+`EINVAL`:: The sockets are not compatible with each other, or not both raw.
+`ENOMEM`:: Insufficient memory is available.
+
+== SEE ALSO
+
+<<nn_errno.3compat#,nn_errno(3compat)>>,
+<<nn_socket.3compat#,nn_socket(3compat)>>,
+<<nng_compat.3compat#,nng_compat(3compat)>>,
+<<nng.7#,nng(7)>>