Add documentation for supplemental functions.

This includes platform portability stuff like mutexes and threads,
etc.  While here we fixed a problem with nng_opts_parse and we
addressed the type of the platform API.

1 files changed, 58 insertions, 0 deletions

diff --git a/docs/man/nng_cv_alloc.3supp.adoc b/docs/man/nng_cv_alloc.3supp.adoc
new file mode 100644
index 00000000..0668298f
--- /dev/null
+++ b/docs/man/nng_cv_alloc.3supp.adoc
@@ -0,0 +1,58 @@
+= nng_cv_alloc(3supp)
+//
+// 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
+
+nng_cv_alloc - allocate condition variable
+
+== SYNOPSIS
+
+[source, c]
+----
+#include <nng/nng.h>
+#include <nng/supplemental/util/platform.h>
+
+typedef struct nng_cv nng_cv;
+
+int nng_cv_alloc(nng_cv **cvp, nng_mtx *mtx);
+----
+
+== DESCRIPTION
+
+The `nng_cv_alloc()` function allocates a condition variable, using
+the mutex _mtx_, and returns it in _cvp_.
+
+Every condition variable is associated with a mutex, which must be
+owned when a thread waits for the condition using
+<<nng_cv_wait.3supp#,`nng_cv_wait()`>> or
+<<nng_cv_until.3supp#,`nng_cv_until()`>>.
+The mutex must also be owned when signaling the condition using the
+<<nng_cv_wake.3supp#,`nng_cv_wake()`>> or
+<<nng_cv_wake1.3supp#,`nng_cv_wake1()`>> functions.
+
+== RETURN VALUES
+
+This function returns 0 on success, and non-zero otherwise.
+
+== ERRORS
+
+`NNG_ENOMEM`:: Insufficient free memory exists.
+
+== SEE ALSO
+
+<<nng_cv_free.3supp#,nng_cv_free(3supp)>>,
+<<nng_cv_until.3supp#,nng_cv_until(3supp)>>,
+<<nng_cv_wait.3supp#,nng_cv_wait(3supp)>>,
+<<nng_cv_wake.3supp#,nng_cv_wake(3supp)>>,
+<<nng_cv_wake1.3supp#,nng_cv_wake1(3supp)>>,
+<<nng_mtx_alloc.3supp#,nng_mtx_alloc(3supp)>>,
+<<nng_strerror.3#,nng_strerror(3)>>,
+<<nng.7#,nng(7)>>