diff --git a/modules/libcom/src/cppStd/epicsAlgorithm.h b/modules/libcom/src/cppStd/epicsAlgorithm.h
index e2043cf26..1920fa4e3 100644
--- a/modules/libcom/src/cppStd/epicsAlgorithm.h
+++ b/modules/libcom/src/cppStd/epicsAlgorithm.h
@@ -12,14 +12,7 @@
  *
  * \brief Contains a few templates out of the C++ standard header algorithm
  *
- * \note The templates are provided here in a much smaller file. Standard algorithm
- * contains many templates for sorting and searching through C++ template containers
- * which are not used in EPICS. If all you need from there is std::min(),
- * std::max() and/or std::swap() your code may compile faster if you include
- * epicsAlgorithm.h and use epicsMin(), epicsMax() and epicsSwap() instead.
- *
- * The C++ standard only requires types to be less-than comparable, so
- * the epicsMin and epicsMax templates only use operator <.
+ * \deprecated Use std::min()/max()/swap() in new code
  */
 
 #ifndef __EPICS_ALGORITHM_H__
diff --git a/modules/libcom/src/misc/dbDefs.h b/modules/libcom/src/misc/dbDefs.h
index 5de0cd922..bda05ed3f 100644
--- a/modules/libcom/src/misc/dbDefs.h
+++ b/modules/libcom/src/misc/dbDefs.h
@@ -73,9 +73,7 @@
 /** \brief Size of a record name without the nil terminator */
 #define PVNAME_SZ (PVNAME_STRINGSZ - 1)
 
-/**
- * \def PVLINK_STRINGSZ
- * \brief Buffer size for the string representation of a DBF_*LINK field
+/** \brief Buffer size for the string representation of a DBF_*LINK field
  */
 #define PVLINK_STRINGSZ 1024
 
diff --git a/modules/libcom/src/misc/epicsExport.h b/modules/libcom/src/misc/epicsExport.h
index 13b27b19e..d1c849eaf 100644
--- a/modules/libcom/src/misc/epicsExport.h
+++ b/modules/libcom/src/misc/epicsExport.h
@@ -35,17 +35,7 @@ extern "C" {
 
 typedef void (*REGISTRAR)(void);
 
-/** \brief Generate a name for an export object.
- * \param typ Object's data type.
- * \param obj Object's name.
- * \return C identifier for the export object.
- */
 #define EPICS_EXPORT_POBJ(typ, obj) pvar_ ## typ ## _ ## obj
-
-/** \brief Generate a name for an export function object.
- * \param fun Function's name.
- * \return C identifier for the export object.
- */
 #define EPICS_EXPORT_PFUNC(fun) EPICS_EXPORT_POBJ(func, fun)
 
 /** \brief Declare an object for exporting.
@@ -79,6 +69,8 @@ typedef void (*REGISTRAR)(void);
  *
  * \param typ Object's data type.
  * \param obj Object's name.
+ *
+ * \note C++ code needs to wrap with @code extern "C" { } @endcode
  */
 #define epicsExportAddress(typ, obj) \
     epicsShareExtern typ *EPICS_EXPORT_POBJ(typ,obj); \
@@ -96,6 +88,8 @@ typedef void (*REGISTRAR)(void);
  \endcode
  *
  * \param fun Registrar function's name.
+ *
+ * \note C++ code needs to wrap with @code extern "C" { } @endcode
  */
 #define epicsExportRegistrar(fun) \
     epicsShareFunc REGISTRAR EPICS_EXPORT_PFUNC(fun) = (REGISTRAR) &fun
@@ -111,6 +105,8 @@ typedef void (*REGISTRAR)(void);
  \endcode
 *
  * \param fun Function's name
+ *
+ * \note C++ code needs to wrap with @code extern "C" { } @endcode
  */
 #define epicsRegisterFunction(fun) \
     static void register_func_ ## fun(void) \
diff --git a/modules/libcom/src/misc/epicsUnitTest.h b/modules/libcom/src/misc/epicsUnitTest.h
index f090eb192..302c87bf5 100644
--- a/modules/libcom/src/misc/epicsUnitTest.h
+++ b/modules/libcom/src/misc/epicsUnitTest.h
@@ -88,14 +88,16 @@
 
 MAIN(iocTest)
 {
-    iocBuildIsolated() || iocRun();
-
-    ... test code ...
-
-    iocShutdown();
-    dbFreeBase(pdbbase);
-    registryFree();
-    pdbbase = NULL;
+    testPlan(0);
+    testdbPrepare();
+    testdbReadDatabase("<dbdname>.dbd", 0, 0);
+    <dbdname>_registerRecordDeviceDriver(pdbbase);
+    testdbReadDatabase("some.db", 0, 0);
+    ... test code before iocInit().  eg. dbGetString() ...
+    testIocInitOk();
+    ... test code with IOC running.  eg. dbGet()
+    testIocShutdownOk();
+    testdbCleanup();
     return testDone();
 }
 \endcode
@@ -235,6 +237,15 @@ LIBCOM_API int  testDiag(const char *fmt, ...)
  */
 LIBCOM_API int  testDone(void);
 
+/** \brief Return non-zero in shared/oversubscribed testing envrionments
+ *
+ * May be used to testSkip(), or select longer timeouts, for some cases
+ * when the test process may be preempted for arbitrarily long times.
+ * This is common in shared CI environments.
+ *
+ * The environment variable $EPICS_TEST_IMPRECISE_TIMING=YES should be
+ * set in by such testing environments.
+ */
 LIBCOM_API
 int testImpreciseTiming(void);
 
diff --git a/modules/libcom/src/osi/epicsEvent.h b/modules/libcom/src/osi/epicsEvent.h
index 9429b9db6..dfa8a4fdf 100644
--- a/modules/libcom/src/osi/epicsEvent.h
+++ b/modules/libcom/src/osi/epicsEvent.h
@@ -20,12 +20,12 @@
  *
  * When creating the consumer thread also create an epicsEvent.
  \code
-   epicsEvent *pevent = new epicsEvent;
+   epicsEvent event;
  \endcode
  * The consumer thread has code containing:
  \code
        while(1) {
-           pevent->wait();
+           pevent.wait();
            while( {more work} ) {
                {process work}
            }
@@ -33,7 +33,7 @@
  \endcode
  * Producers create requests and issue the statement:
  \code
-       pevent->trigger();
+       pevent.trigger();
  \endcode
  **/
 
diff --git a/modules/libcom/src/osi/epicsMutex.h b/modules/libcom/src/osi/epicsMutex.h
index af27f2f96..6c79fd9e0 100644
--- a/modules/libcom/src/osi/epicsMutex.h
+++ b/modules/libcom/src/osi/epicsMutex.h
@@ -19,12 +19,18 @@
  *
  * The typical C++ use of a mutual exclusion semaphore is:
  \code
-     epicsMutex *plock = new epicsMutex;
+     epicsMutex lock;
      ...
      ...
-     plock->lock();
-     // process resources
-     plock->unlock();
+     {
+         epicsMutex::guard_t G(lock); // lock
+         // process resources
+     } // unlock
+     // or for compatiblity
+     {
+         epicsGuard<epicsMutex> G(lock); // lock
+         // process resources
+     } // unlock
  \endcode
  *
  * \note The implementation:
diff --git a/modules/libcom/src/osi/epicsTime.h b/modules/libcom/src/osi/epicsTime.h
index a1ccf382d..fcfa679a5 100644
--- a/modules/libcom/src/osi/epicsTime.h
+++ b/modules/libcom/src/osi/epicsTime.h
@@ -155,10 +155,10 @@ public:
     static epicsTime getCurrent ();
     /** \brief Get current monotonic time
      *
-     * Returns an epicsTime containing the current monotonic time, a
-     * high-resolution OS clock that counts at a steady rate, never
-     * going backwards or jumping forwards. This time is only useful
-     * for measuring time differences.
+     * Returns an epicsTime containing the current monotonic time, an
+     * OS clock which never going backwards or jumping forwards.
+     * This time is has an undefined epoch, and is only useful for
+     * measuring time differences.
      */
     static epicsTime getMonotonic ();