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, 89 insertions, 0 deletions

diff --git a/docs/man/nng_cv_until.3supp.adoc b/docs/man/nng_cv_until.3supp.adoc
new file mode 100644
index 00000000..4d39ecc0
--- /dev/null
+++ b/docs/man/nng_cv_until.3supp.adoc
@@ -0,0 +1,89 @@
+= nng_cv_until(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_until - wait for condition or timeout
+
+== SYNOPSIS
+
+[source, c]
+----
+#include <nng/nng.h>
+#include <nng/supplemental/util/platform.h>
+
+int nng_cv_wait(nng_cv *cv, nng_time when);
+----
+
+== DESCRIPTION
+
+The `nng_cv_until()` waits until either the condition variable _cv_ is signaled
+by another thread calling either <<nng_cv_wake.3supp#,`nng_cv_wake()`>> or
+<<nng_cv_wake1.3supp#,`nng_cv_wake1()`>>, or the system clock (as tracked
+by <<nng_clock.3supp#,`nng_clock()`>>) reaches _when_.
+
+The caller must have have ownership of the mutex that was used when
+_cv_ was allocated.
+This function will drop the ownership of that mutex, and reacquire it
+atomically just before returning to the caller.
+(The waiting is done without holding the mutex.)
+
+NOTE: Any condition may be used or checked, but the condition must be
+checked, as it is possible for this function to wake up "`spuriously`".
+The best way to do this is inside a loop that repeats until the condition
+tests for true.
+
+== EXAMPLE
+
+The following example demonstrates use of this function:
+
+.Example 1: Waiting for the condition
+[source, c]
+----
+
+    nng_mtx_lock(m);  // assume cv was allocated using m
+    while (!condition_true) {
+        if (nng_cv_wait(cv) == NNG_ETIMEDOUT) {
+            printf("Time out reached!\n");
+            break;
+        }
+    }
+    // condition_true is true
+    nng_mtx_unlock(m);
+----
+
+.Example 2: Signaling the condition
+[source, c]
+----
+    nng_mtx_lock(m);
+    condition_true = true;
+    cv_wake(cv);
+    nng_mtx_unlock(m);
+----
+
+== RETURN VALUES
+
+None.
+
+== ERRORS
+
+None.
+
+== SEE ALSO
+
+<<nng_cv_alloc.3supp#,nng_cv_alloc(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_mtx_lock.3supp#,nng_mtx_lock(3supp)>>,
+<<nng_mtx_unlock.3supp#,nng_mtx_unlock(3supp)>>,
+<<nng.7#,nng(7)>>