diff --git a/src/libCom/iocsh/iocsh.cpp b/src/libCom/iocsh/iocsh.cpp
index 671239781..d8701532e 100644
--- a/src/libCom/iocsh/iocsh.cpp
+++ b/src/libCom/iocsh/iocsh.cpp
@@ -56,7 +56,8 @@ static struct iocshVariable *iocshVariableHead;
 static char iocshVarID[] = "iocshVar";
 extern "C" { static void varCallFunc(const iocshArgBuf *); }
 static epicsMutexId iocshTableMutex;
-static epicsThreadOnceId iocshTableOnceId = EPICS_THREAD_ONCE_INIT;
+static epicsThreadOnceId iocshOnceId = EPICS_THREAD_ONCE_INIT;
+static epicsThreadPrivateId iocshMacroHandleId;
 
 /*
  * I/O redirection
@@ -71,11 +72,17 @@ struct iocshRedirect {
 };
 
 /*
- * Set up command table mutex
+ * Set up module variables
  */
-static void iocshTableOnce (void *)
+static void iocshOnce (void *)
 {
     iocshTableMutex = epicsMutexMustCreate ();
+    iocshMacroHandleId = epicsThreadPrivateCreate();
+}
+
+static void iocshInit (void)
+{
+    epicsThreadOnce (&iocshOnceId, iocshOnce, NULL);
 }
 
 /*
@@ -84,7 +91,7 @@ static void iocshTableOnce (void *)
 static void
 iocshTableLock (void)
 {
-    epicsThreadOnce (&iocshTableOnceId, iocshTableOnce, NULL);
+    iocshInit();
     epicsMutexMustLock (iocshTableMutex);
 }
 
@@ -94,7 +101,6 @@ iocshTableLock (void)
 static void
 iocshTableUnlock (void)
 {
-    epicsThreadOnce (&iocshTableOnceId, iocshTableOnce, NULL);
     epicsMutexUnlock (iocshTableMutex);
 }
 
@@ -475,7 +481,7 @@ static void helpCallFunc(const iocshArgBuf *args)
  * The body of the command interpreter
  */
 static int
-iocshBody (const char *pathname, const char *commandLine)
+iocshBody (const char *pathname, const char *commandLine, const char *macros)
 {
     FILE *fp = NULL;
     const char *filename = NULL;
@@ -498,7 +504,12 @@ iocshBody (const char *pathname, const char *commandLine)
     struct iocshCommand *found;
     void *readlineContext = NULL;
     int wasOkToBlock;
+    static const char * pairs[] = {"", "environ", NULL, NULL};
+    MAC_HANDLE *handle;
+    char ** defines = NULL;
     
+    iocshInit();
+
     /*
      * See if command interpreter is interactive
      */
@@ -540,7 +551,35 @@ iocshBody (const char *pathname, const char *commandLine)
         fprintf(epicsGetStderr(), "Out of memory!\n");
         return -1;
     }
-
+    
+    /*
+     * Parse macro definitions, this check occurs before creating the
+     * macro handle to simplify cleanup.
+     */
+    
+    if (macros) {
+        if (macParseDefns(NULL, macros, &defines) < 0) {
+            return -1;
+        }
+    }
+    
+    /*
+     * Check for existing macro context or construct a new one.
+     */
+    handle = (MAC_HANDLE *) epicsThreadPrivateGet(iocshMacroHandleId);
+    
+    if (handle == NULL) {
+        if (macCreateHandle(&handle, pairs)) {
+            errlogMessage("iocsh: macCreateHandle failed.");
+            return -1;
+        }
+        
+        epicsThreadPrivateSet(iocshMacroHandleId, (void *) handle);
+    }
+    
+    macPushScope(handle);
+    macInstallMacros(handle, defines);
+    
     /*
      * Read commands till EOF or exit
      */
@@ -585,7 +624,7 @@ iocshBody (const char *pathname, const char *commandLine)
          * Expand macros
          */
         free(line);
-        if ((line = macEnvExpand(raw)) == NULL)
+        if ((line = macDefExpand(raw, handle)) == NULL)
             continue;
 
         /*
@@ -744,7 +783,7 @@ iocshBody (const char *pathname, const char *commandLine)
             if (openRedirect(filename, lineno, redirects) < 0)
                 continue;
             startRedirect(filename, lineno, redirects);
-            iocshBody(commandFile, NULL);
+            iocshBody(commandFile, NULL, macros);
             stopRedirect(filename, lineno, redirects);
             continue;
         }
@@ -811,6 +850,12 @@ iocshBody (const char *pathname, const char *commandLine)
         }
         stopRedirect(filename, lineno, redirects);
     }
+    macPopScope(handle);
+    
+    if (handle->level == 0) {
+        macDeleteHandle(handle);
+        epicsThreadPrivateSet(iocshMacroHandleId, NULL);
+    }
     if (fp && (fp != stdin))
         fclose (fp);
     if (redirects != NULL) {
@@ -833,17 +878,58 @@ iocshBody (const char *pathname, const char *commandLine)
 int epicsShareAPI
 iocsh (const char *pathname)
 {
-    if (pathname)
-        epicsEnvSet("IOCSH_STARTUP_SCRIPT", pathname);
-    return iocshBody(pathname, NULL);
+    return iocshLoad(pathname, NULL);
 }
 
 int epicsShareAPI
 iocshCmd (const char *cmd)
+{
+    return iocshRun(cmd, NULL);
+}
+
+int epicsShareAPI
+iocshLoad(const char *pathname, const char *macros)
+{
+    if (pathname)
+        epicsEnvSet("IOCSH_STARTUP_SCRIPT", pathname);
+    return iocshBody(pathname, NULL, macros);
+}
+
+int epicsShareAPI
+iocshRun(const char *cmd, const char *macros)
 {
     if (cmd == NULL)
         return 0;
-    return iocshBody(NULL, cmd);
+    return iocshBody(NULL, cmd, macros);
+}
+
+/*
+ * Needed to work around the necessary limitations of macLib and
+ * environment variables. In every other case of macro expansion
+ * it is the expected outcome that defined macros override any
+ * environment variables. 
+ *
+ * iocshLoad/Run turn this on its head as it is very likely that 
+ * an epicsEnvSet command may be run within the context of their 
+ * calls. Thus, it would be expected that the new value would be 
+ * returned in any future macro expansion.
+ *
+ * To do so, the epicsEnvSet command needs to be able to access
+ * and update the shared MAC_HANDLE that the iocsh uses. Which is
+ * what this function is provided for.
+ */
+void epicsShareAPI
+iocshEnvClear(const char *name)
+{
+    MAC_HANDLE *handle;
+    
+    if (iocshMacroHandleId) {
+        handle = (MAC_HANDLE *) epicsThreadPrivateGet(iocshMacroHandleId);
+    
+        if (handle != NULL) {
+            macPutValue(handle, name, NULL);
+        }
+    }
 }
 
 /*
@@ -926,6 +1012,26 @@ static void iocshCmdCallFunc(const iocshArgBuf *args)
     iocshCmd(args[0].sval);
 }
 
+/* iocshLoad */
+static const iocshArg iocshLoadArg0 = { "pathname",iocshArgString};
+static const iocshArg iocshLoadArg1 = { "macros", iocshArgString};
+static const iocshArg *iocshLoadArgs[2] = {&iocshLoadArg0, &iocshLoadArg1};
+static const iocshFuncDef iocshLoadFuncDef = {"iocshLoad",2,iocshLoadArgs};
+static void iocshLoadCallFunc(const iocshArgBuf *args)
+{
+    iocshLoad(args[0].sval, args[1].sval);
+}
+
+/* iocshRun */
+static const iocshArg iocshRunArg0 = { "command",iocshArgString};
+static const iocshArg iocshRunArg1 = { "macros", iocshArgString};
+static const iocshArg *iocshRunArgs[2] = {&iocshRunArg0, &iocshRunArg1};
+static const iocshFuncDef iocshRunFuncDef = {"iocshRun",2,iocshRunArgs};
+static void iocshRunCallFunc(const iocshArgBuf *args)
+{
+    iocshRun(args[0].sval, args[1].sval);
+}
+
 /*
  * Dummy internal commands -- register and install in command table
  * so they show up in the help display
@@ -953,6 +1059,8 @@ static void localRegister (void)
     iocshRegister(&exitFuncDef,exitCallFunc);
     iocshRegister(&helpFuncDef,helpCallFunc);
     iocshRegister(&iocshCmdFuncDef,iocshCmdCallFunc);
+    iocshRegister(&iocshLoadFuncDef,iocshLoadCallFunc);
+    iocshRegister(&iocshRunFuncDef,iocshRunCallFunc);
 }
 
 } /* extern "C" */
diff --git a/src/libCom/iocsh/iocsh.h b/src/libCom/iocsh/iocsh.h
index d89991050..e31756479 100644
--- a/src/libCom/iocsh/iocsh.h
+++ b/src/libCom/iocsh/iocsh.h
@@ -70,6 +70,11 @@ epicsShareFunc void epicsShareAPI iocshFree(void);
 
 epicsShareFunc int epicsShareAPI iocsh(const char *pathname);
 epicsShareFunc int epicsShareAPI iocshCmd(const char *cmd);
+epicsShareFunc int epicsShareAPI iocshLoad(const char *pathname, const char* macros);
+epicsShareFunc int epicsShareAPI iocshRun(const char *cmd, const char* macros);
+
+/* Makes macros that shadow environment variables work correctly with epicsEnvSet */
+epicsShareFunc void epicsShareAPI iocshEnvClear(const char *name);
 
 /* 'weak' link to pdbbase */
 epicsShareExtern struct dbBase **iocshPpdbbase;
diff --git a/src/libCom/macLib/macCore.c b/src/libCom/macLib/macCore.c
index da5244dfd..02c8da765 100644
--- a/src/libCom/macLib/macCore.c
+++ b/src/libCom/macLib/macCore.c
@@ -103,7 +103,7 @@ epicsShareAPI macCreateHandle(
     MAC_HANDLE  **pHandle,      /* address of variable to receive pointer */
                                 /* to new macro substitution context */
 
-    char        *pairs[] )      /* pointer to NULL-terminated array of */
+    const char * pairs[] )      /* pointer to NULL-terminated array of */
                                 /* {name,value} pair strings; a NULL */
                                 /* value implies undefined; a NULL */
                                 /* argument implies no macros */
@@ -253,9 +253,18 @@ epicsShareAPI macPutValue(
     /* handle NULL value case: if name was found, delete entry (may be
        several entries at different scoping levels) */
     if ( value == NULL ) {
-        /* FIXME: shouldn't be able to delete entries from lower scopes */
-        while ( ( entry = lookup( handle, name, FALSE ) ) != NULL )
+        /* 
+         * FIXME: shouldn't be able to delete entries from lower scopes
+         * NOTE: when this is changed, this functionality of removing
+         * a macro from all scopes will still be needed by iocshEnvClear
+         */
+        while ( ( entry = lookup( handle, name, FALSE ) ) != NULL ) {
             delete( handle, entry );
+            
+            if (strcmp(entry->type, "environment variable") == 0)
+                break;
+        }
+        
         return 0;
     }
 
diff --git a/src/libCom/macLib/macEnv.c b/src/libCom/macLib/macEnv.c
index 35872d14c..8cdf8bd94 100644
--- a/src/libCom/macLib/macEnv.c
+++ b/src/libCom/macLib/macEnv.c
@@ -20,16 +20,26 @@
 
 char * epicsShareAPI
 macEnvExpand(const char *str)
+{
+    return macDefExpand(str, NULL);
+}
+
+char * epicsShareAPI
+macDefExpand(const char *str, MAC_HANDLE *macros)
 {
     MAC_HANDLE *handle;
-    static char *pairs[] = { "", "environ", NULL, NULL };
+    static const char * pairs[] = { "", "environ", NULL, NULL };
     long destCapacity = 128;
     char *dest = NULL;
     int n;
-
-    if (macCreateHandle(&handle, pairs)){
-        errlogMessage("macEnvExpand: macCreateHandle failed.");
-        return NULL;
+    
+    if (macros) {
+        handle = macros;
+    } else {
+        if (macCreateHandle(&handle, pairs)){
+            errlogMessage("macDefExpand: macCreateHandle failed.");
+            return NULL;
+        }
     }
 
     do {
@@ -57,7 +67,10 @@ macEnvExpand(const char *str)
     }
 
 done:
-    if (macDeleteHandle(handle))
-        errlogMessage("macEnvExpand: macDeleteHandle failed.");
+    if (macros == NULL) {
+        if (macDeleteHandle(handle)) {
+            errlogMessage("macDefExpand: macDeleteHandle failed.");
+        }
+    }
     return dest;
 }
diff --git a/src/libCom/macLib/macLib.h b/src/libCom/macLib/macLib.h
index a99007e9a..c06e67d9e 100644
--- a/src/libCom/macLib/macLib.h
+++ b/src/libCom/macLib/macLib.h
@@ -52,7 +52,7 @@ epicsShareAPI macCreateHandle(
     MAC_HANDLE  **handle,       /* address of variable to receive pointer */
                                 /* to new macro substitution context */
 
-    char        *pairs[]        /* pointer to NULL-terminated array of */
+    const char * pairs[]        /* pointer to NULL-terminated array of */
                                 /* {name,value} pair strings; a NULL */
                                 /* value implies undefined; a NULL */
                                 /* argument implies no macros */
@@ -151,6 +151,13 @@ epicsShareAPI macEnvExpand(
     const char *str             /* string to be expanded */
 );
 
+epicsShareFunc char *           /* expanded string; NULL if any undefined macros */
+epicsShareAPI macDefExpand(
+    const char *str,            /* string to be expanded */
+    MAC_HANDLE *macros          /* opaque handle; can be NULL if default */
+                                /* special characters are to be used */
+);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/libCom/macLib/macLibREADME b/src/libCom/macLib/macLibREADME
index ec521d8a6..f3cda53c2 100644
--- a/src/libCom/macLib/macLibREADME
+++ b/src/libCom/macLib/macLibREADME
@@ -164,7 +164,14 @@ d) char *macEnvExpand( char *src );
    pointer to this null-terminated string. It returns NULL if the source
    string contains any undefined references.
 
-e) long macReportMacros( MAC_HANDLE *handle );
+e) char *macDefExpand( char *src, MAC_HANDLE *macros );
+
+   This operates in the same manner as macEnvExpand, but takes an 
+   optional macro handle that can contain a set of macro definitions. 
+   These macros are appended to the set of macros from environment 
+   variables when expanding the string. 
+
+f) long macReportMacros( MAC_HANDLE *handle );
 
    This reports details of current definitions to standard output, and is
    intended purely for debugging purposes.
diff --git a/src/libCom/osi/os/Darwin/osdEnv.c b/src/libCom/osi/os/Darwin/osdEnv.c
index 44c0afa0a..35517c1e9 100644
--- a/src/libCom/osi/os/Darwin/osdEnv.c
+++ b/src/libCom/osi/os/Darwin/osdEnv.c
@@ -1,7 +1,6 @@
 /*************************************************************************\
 * Copyright (c) 2002 The University of Saskatchewan
-* EPICS BASE Versions 3.13.7
-* and higher are distributed subject to a Software License Agreement found
+* EPICS BASE is distributed subject to a Software License Agreement found
 * in file LICENSE that is included with this distribution. 
 \*************************************************************************/
 /* osdEnv.c */
@@ -30,13 +29,15 @@
 
 #define epicsExportSharedSymbols
 #include "epicsStdio.h"
-#include <envDefs.h>
+#include "envDefs.h"
+#include "iocsh.h"
 
 /*
  * Set the value of an environment variable
  */
 epicsShareFunc void epicsShareAPI epicsEnvSet (const char *name, const char *value)
 {
+    iocshEnvClear(name);
     setenv(name, value, 1);
 }
 
diff --git a/src/libCom/osi/os/default/osdEnv.c b/src/libCom/osi/os/default/osdEnv.c
index ff1675fda..6c67a6999 100644
--- a/src/libCom/osi/os/default/osdEnv.c
+++ b/src/libCom/osi/os/default/osdEnv.c
@@ -1,7 +1,6 @@
 /*************************************************************************\
 * Copyright (c) 2002 The University of Saskatchewan
-* EPICS BASE Versions 3.13.7
-* and higher are distributed subject to a Software License Agreement found
+* EPICS BASE is distributed subject to a Software License Agreement found
 * in file LICENSE that is included with this distribution. 
 \*************************************************************************/
 /* osdEnv.c */
@@ -23,11 +22,12 @@
 
 #define epicsExportSharedSymbols
 #include "epicsStdio.h"
-#include <errlog.h>
-#include <cantProceed.h>
-#include <envDefs.h>
-#include <osiUnistd.h>
+#include "errlog.h"
+#include "cantProceed.h"
+#include "envDefs.h"
+#include "osiUnistd.h"
 #include "epicsFindSymbol.h"
+#include "iocsh.h"
 
 /*
  * Set the value of an environment variable
@@ -38,6 +38,8 @@ epicsShareFunc void epicsShareAPI epicsEnvSet (const char *name, const char *val
 {
     char *cp;
 
+    iocshEnvClear(name);
+    
 	cp = mallocMustSucceed (strlen (name) + strlen (value) + 2, "epicsEnvSet");
 	strcpy (cp, name);
 	strcat (cp, "=");
diff --git a/src/libCom/osi/os/iOS/osdEnv.c b/src/libCom/osi/os/iOS/osdEnv.c
index f55b174a8..c631ec4f8 100644
--- a/src/libCom/osi/os/iOS/osdEnv.c
+++ b/src/libCom/osi/os/iOS/osdEnv.c
@@ -28,32 +28,15 @@
 #include <envDefs.h>
 #include <osiUnistd.h>
 #include "epicsFindSymbol.h"
-
+#include <iocsh.h>
 
 /*
  * Set the value of an environment variable
- * Leaks memory, but the assumption is that this routine won't be
- * called often enough for the leak to be a problem.
  */
 epicsShareFunc void epicsShareAPI epicsEnvSet (const char *name, const char *value)
 {
-    char *cp;
-
-	cp = mallocMustSucceed (strlen (name) + strlen (value) + 2, "epicsEnvSet");
-	strcpy (cp, name);
-	strcat (cp, "=");
-	strcat (cp, value);
-	if (putenv (cp) < 0) {
-		errPrintf(
-                -1L,
-                __FILE__,
-                __LINE__,
-                "Failed to set environment parameter \"%s\" to \"%s\": %s\n",
-                name,
-                value,
-                strerror (errno));
-        free (cp);
-	}
+    iocshEnvClear(name);
+    setenv(name, value, 1);
 }
 
 /*
diff --git a/src/libCom/osi/os/vxWorks/osdEnv.c b/src/libCom/osi/os/vxWorks/osdEnv.c
index e41d57440..085611935 100644
--- a/src/libCom/osi/os/vxWorks/osdEnv.c
+++ b/src/libCom/osi/os/vxWorks/osdEnv.c
@@ -23,12 +23,12 @@
 #include <ctype.h>
 #include <envLib.h>
 
-#include "epicsStdio.h"
-#include <errlog.h>
-#include <cantProceed.h>
-
 #define epicsExportSharedSymbols
+#include "cantProceed.h"
 #include "epicsFindSymbol.h"
+#include "epicsStdio.h"
+#include "errlog.h"
+#include "iocsh.h"
 
 /*
  * Set the value of an environment variable
@@ -39,21 +39,18 @@ epicsShareFunc void epicsShareAPI epicsEnvSet (const char *name, const char *val
 {
     char *cp;
 
-	cp = mallocMustSucceed (strlen (name) + strlen (value) + 2, "epicsEnvSet");
-	strcpy (cp, name);
-	strcat (cp, "=");
-	strcat (cp, value);
-	if (putenv (cp) < 0) {
-		errPrintf(
-                -1L,
-                __FILE__,
-                __LINE__,
-                "Failed to set environment parameter \"%s\" to \"%s\": %s\n",
-                name,
-                value,
-                strerror (errno));
+    iocshEnvClear(name);
+    
+    cp = mallocMustSucceed (strlen (name) + strlen (value) + 2, "epicsEnvSet");
+    strcpy (cp, name);
+    strcat (cp, "=");
+    strcat (cp, value);
+    if (putenv (cp) < 0) {
+        errPrintf(-1L, __FILE__, __LINE__,
+            "Failed to set environment parameter \"%s\" to \"%s\": %s\n",
+            name, value, strerror (errno));
         free (cp);
-	}
+    }
 }
 
 /*
diff --git a/src/libCom/test/Makefile b/src/libCom/test/Makefile
index 62f73c3e2..3a3d32a8f 100755
--- a/src/libCom/test/Makefile
+++ b/src/libCom/test/Makefile
@@ -163,10 +163,10 @@ epicsExceptionTest_SRCS += epicsExceptionTest.cpp
 testHarness_SRCS += epicsExceptionTest.cpp
 TESTS += epicsExceptionTest
 
-TESTPROD_HOST += macEnvExpandTest
-macEnvExpandTest_SRCS += macEnvExpandTest.c
-testHarness_SRCS += macEnvExpandTest.c
-TESTS += macEnvExpandTest
+TESTPROD_HOST += macDefExpandTest
+macDefExpandTest_SRCS += macDefExpandTest.c
+testHarness_SRCS += macDefExpandTest.c
+TESTS += macDefExpandTest
 
 TESTPROD_HOST += macLibTest
 macLibTest_SRCS += macLibTest.c
diff --git a/src/libCom/test/epicsRunLibComTests.c b/src/libCom/test/epicsRunLibComTests.c
index cf4a2dd7f..5bf6cafd1 100644
--- a/src/libCom/test/epicsRunLibComTests.c
+++ b/src/libCom/test/epicsRunLibComTests.c
@@ -44,7 +44,7 @@ int epicsThreadTest(void);
 int epicsTimerTest(void);
 int epicsTimeTest(void);
 int epicsTypesTest(void);
-int macEnvExpandTest(void);
+int macDefExpandTest(void);
 int macLibTest(void);
 int ringBytesTest(void);
 int ringPointerTest(void);
@@ -92,7 +92,7 @@ void epicsRunLibComTests(void)
     runTest(epicsThreadPrivateTest);
     runTest(epicsTimeTest);
     runTest(epicsTypesTest);
-    runTest(macEnvExpandTest);
+    runTest(macDefExpandTest);
     runTest(macLibTest);
     runTest(ringBytesTest);
     runTest(ringPointerTest);
diff --git a/src/libCom/test/macDefExpandTest.c b/src/libCom/test/macDefExpandTest.c
new file mode 100644
index 000000000..6114e92a0
--- /dev/null
+++ b/src/libCom/test/macDefExpandTest.c
@@ -0,0 +1,256 @@
+/*************************************************************************\
+* Copyright (c) 2014 UChicago Argonne LLC, as Operator of Argonne
+*     National Laboratory.
+* Copyright (c) 2002 The Regents of the University of California, as
+*     Operator of Los Alamos National Laboratory.
+* EPICS BASE is distributed subject to a Software License Agreement found
+* in file LICENSE that is included with this distribution.
+\*************************************************************************/
+/*
+ * $Revision-Id$
+ */
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#include "macLib.h"
+#include "envDefs.h"
+#include "errlog.h"
+#include "epicsUnitTest.h"
+#include "testMain.h"
+
+
+static void checkMac(MAC_HANDLE *handle, const char *name, const char *value)
+{
+    char buf[20];
+
+    buf[19]='\0';
+    if(macGetValue(handle, name, buf, 19)<0) {
+        if(value)
+            testFail("Macro %s undefined, expected %s", name, value);
+        else
+            testPass("Macro %s undefined", name);
+    } else {
+        if(!value)
+            testFail("Macro %s is %s, expected undefined", name, buf);
+        else if(strcmp(value, buf)==0)
+            testPass("Macro %s is %s", name, value);
+        else
+            testFail("Macro %s is %s, expected %s", name, buf, value);
+    }
+}
+
+static void macEnvScope(void)
+{
+    MAC_HANDLE *handle;
+    char **defines;
+    static const char *pairs[] = { "", "environ", NULL, NULL };
+
+    epicsEnvSet("C","3");
+    epicsEnvSet("D","4");
+    epicsEnvSet("E","5");
+
+    macCreateHandle(&handle, pairs);
+    macParseDefns(NULL, "A=1,B=2,E=15", &defines);
+    macInstallMacros(handle, defines);
+
+    checkMac(handle, "A", "1");
+    checkMac(handle, "B", "2");
+    checkMac(handle, "C", "3");
+    checkMac(handle, "D", "4");
+    checkMac(handle, "E", "15");
+    checkMac(handle, "F", NULL);
+
+    {
+        macPushScope(handle);
+
+        macParseDefns(NULL, "A=11,C=13,D=14,G=7", &defines);
+        macInstallMacros(handle, defines);
+
+        checkMac(handle, "A", "11");
+        checkMac(handle, "B", "2");
+        checkMac(handle, "C", "13");
+        checkMac(handle, "D", "14");
+        checkMac(handle, "E", "15");
+        checkMac(handle, "F", NULL);
+        checkMac(handle, "G", "7");
+
+        epicsEnvSet("D", "24");
+        macPutValue(handle, "D", NULL); /* implicit when called through in iocshBody */
+        epicsEnvSet("F", "6");
+        macPutValue(handle, "F", NULL); /* implicit */
+        epicsEnvSet("G", "17");
+        macPutValue(handle, "G", NULL); /* implicit */
+
+        checkMac(handle, "D", "24");
+        checkMac(handle, "F", "6");
+        checkMac(handle, "G", "17");
+
+        macPopScope(handle);
+    }
+
+    checkMac(handle, "A", "1");
+    checkMac(handle, "B", "2");
+    checkMac(handle, "C", "3");
+    checkMac(handle, "D", "24");
+    checkMac(handle, "E", "15");
+    checkMac(handle, "F", "6");
+    checkMac(handle, "G", "17");
+
+    {
+        macPushScope(handle);
+
+        macParseDefns(NULL, "D=34,G=27", &defines);
+        macInstallMacros(handle, defines);
+
+        checkMac(handle, "D", "34");
+        checkMac(handle, "G", "27");
+
+        macPopScope(handle);
+    }
+
+    checkMac(handle, "D", "24");
+
+    macDeleteHandle(handle);
+}
+
+static void check(const char *str, const char *macros, const char *expect)
+{
+    MAC_HANDLE *handle;
+    char **defines;
+    static const char *pairs[] = { "", "environ", NULL, NULL };
+    
+    macCreateHandle(&handle, pairs);
+    macParseDefns(NULL, macros, &defines);
+    macInstallMacros(handle, defines);
+    
+    char *got = macDefExpand(str, handle);
+    int pass = -1;
+
+    if (expect && !got) {
+        testDiag("Got NULL, expected \"%s\".\n", expect);
+        pass = 0;
+    }
+    else if (!expect && got) {
+        testDiag("Got \"%s\", expected NULL.\n", got);
+        pass = 0;
+    }
+    else if (expect && got && strcmp(got, expect)) {
+        testDiag("Got \"%s\", expected \"%s\".\n", got, expect);
+        pass = 0;
+    }
+    testOk(pass, "%s", str);
+    
+    macDeleteHandle(handle);
+}
+
+MAIN(macDefExpandTest)
+{
+    eltc(0);
+    testPlan(97);
+
+    check("FOO", "", "FOO");
+
+    check("${FOO}", "", NULL);
+    check("${FOO,BAR}", "", NULL);
+    check("${FOO,BAR=baz}", "", NULL);
+    check("${FOO,BAR=$(FOO)}", "", NULL);
+    check("${FOO,FOO}", "", NULL);
+    check("${FOO,FOO=$(FOO)}", "", NULL);
+    check("${FOO,BAR=baz,FUM}", "", NULL);
+
+    check("${=}", "", "");
+    check("x${=}y", "", "xy");
+
+    check("${,=}", "", "");
+    check("x${,=}y", "", "xy");
+
+    check("${FOO=}", "", "");
+    check("x${FOO=}y", "", "xy");
+
+    check("${FOO=,}", "", "");
+    check("x${FOO=,}y", "", "xy");
+
+    check("${FOO,FOO=}", "", "");
+    check("x${FOO,FOO=}y", "", "xy");
+
+    check("${FOO=,BAR}", "", "");
+    check("x${FOO=,BAR}y", "", "xy");
+
+    check("${FOO=$(BAR=)}", "", "");
+    check("x${FOO=$(BAR=)}y", "", "xy");
+
+    check("${FOO=,BAR=baz}", "", "");
+    check("x${FOO=,BAR=baz}y", "", "xy");
+
+    check("${FOO=$(BAR),BAR=}", "", "");
+    check("x${FOO=$(BAR),BAR=}y", "", "xy");
+
+    check("${=BAR}", "", "BAR");
+    check("x${=BAR}y", "", "xBARy");
+
+    check("${FOO=BAR}", "", "BAR");
+    check("x${FOO=BAR}y", "", "xBARy");
+
+    epicsEnvSet("FOO","BLETCH");
+    check("${FOO}", "", "BLETCH");
+    check("${FOO,FOO}", "", "BLETCH");
+    check("x${FOO}y", "", "xBLETCHy");
+    check("x${FOO}y${FOO}z", "", "xBLETCHyBLETCHz");
+    check("${FOO=BAR}", "", "BLETCH");
+    check("x${FOO=BAR}y", "", "xBLETCHy");
+    check("${FOO=${BAZ}}", "", "BLETCH");
+    check("${FOO=${BAZ},BAR=$(BAZ)}", "", "BLETCH");
+    check("x${FOO=${BAZ}}y", "", "xBLETCHy");
+    check("x${FOO=${BAZ},BAR=$(BAZ)}y", "", "xBLETCHy");
+    check("${BAR=${FOO}}", "", "BLETCH");
+    check("x${BAR=${FOO}}y", "", "xBLETCHy");
+    check("w${BAR=x${FOO}y}z", "", "wxBLETCHyz");
+
+    check("${FOO,FOO=BAR}", "", "BAR");
+    check("x${FOO,FOO=BAR}y", "", "xBARy");
+    check("${BAR,BAR=$(FOO)}", "", "BLETCH");
+    check("x${BAR,BAR=$(FOO)}y", "", "xBLETCHy");
+    check("${BAR,BAR=$($(FOO)),BLETCH=GRIBBLE}", "", "GRIBBLE");
+    check("x${BAR,BAR=$($(FOO)),BLETCH=GRIBBLE}y", "", "xGRIBBLEy");
+    check("${$(BAR,BAR=$(FOO)),BLETCH=GRIBBLE}", "", "GRIBBLE");
+    check("x${$(BAR,BAR=$(FOO)),BLETCH=GRIBBLE}y", "", "xGRIBBLEy");
+
+    check("${FOO}/${BAR}", "BAR=GLEEP", "BLETCH/GLEEP");
+    check("x${FOO}/${BAR}y", "BAR=GLEEP", "xBLETCH/GLEEPy");
+    check("${FOO,BAR}/${BAR}", "BAR=GLEEP", "BLETCH/GLEEP");
+    check("${FOO,BAR=x}/${BAR}", "BAR=GLEEP", "BLETCH/GLEEP");
+    check("${BAZ=BLETCH,BAR}/${BAR}", "BAR=GLEEP", "BLETCH/GLEEP");
+    check("${BAZ=BLETCH,BAR=x}/${BAR}", "BAR=GLEEP", "BLETCH/GLEEP");
+    
+    check("${${FOO}}", "BAR=GLEEP,BLETCH=BAR", "BAR");
+    check("x${${FOO}}y", "BAR=GLEEP,BLETCH=BAR", "xBARy");
+    check("${${FOO}=GRIBBLE}", "BAR=GLEEP,BLETCH=BAR", "BAR");
+    check("x${${FOO}=GRIBBLE}y", "BAR=GLEEP,BLETCH=BAR", "xBARy");
+
+    check("${${FOO}}", "BAR=GLEEP,BLETCH=${BAR}", "GLEEP");
+
+    epicsEnvSet("FOO","${BAR}");
+    check("${FOO}", "BAR=GLEEP,BLETCH=${BAR}" ,"GLEEP");
+
+    check("${FOO}", "BAR=${BAZ},BLETCH=${BAR}", NULL);
+
+    check("${FOO}", "BAR=${BAZ=GRIBBLE},BLETCH=${BAR}", "GRIBBLE");
+
+    check("${FOO}", "BAR=${STR1},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", "VAL1");
+
+    check("${FOO}", "BAR=${STR2},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", "VAL2");
+
+    check("${FOO}", "BAR=${FOO},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", NULL);
+    check("${FOO,FOO=$(FOO)}", "BAR=${FOO},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", NULL);
+    check("${FOO=$(FOO)}", "BAR=${FOO},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", NULL);
+    check("${FOO=$(BAR),BAR=$(FOO)}", "BAR=${FOO},BLETCH=${BAR},STR1=VAL1,STR2=VAL2", NULL);
+
+    macEnvScope();
+    
+    errlogFlush();
+    eltc(1);
+    return testDone();
+}
diff --git a/src/libCom/test/macEnvExpandTest.c b/src/libCom/test/macEnvExpandTest.c
deleted file mode 100644
index b56cc366a..000000000
--- a/src/libCom/test/macEnvExpandTest.c
+++ /dev/null
@@ -1,159 +0,0 @@
-/*************************************************************************\
-* Copyright (c) 2006 UChicago Argonne LLC, as Operator of Argonne
-*     National Laboratory.
-* Copyright (c) 2002 The Regents of the University of California, as
-*     Operator of Los Alamos National Laboratory.
-* EPICS BASE is distributed subject to a Software License Agreement found
-* in file LICENSE that is included with this distribution.
-\*************************************************************************/
-/*
- * $Revision-Id$
- */
-
-#include <stddef.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-
-#include "macLib.h"
-#include "envDefs.h"
-#include "errlog.h"
-#include "epicsUnitTest.h"
-#include "testMain.h"
-
-static void check(const char *str, const char *expect)
-{
-    char *got = macEnvExpand(str);
-    int pass = -1;
-
-    if (expect && !got) {
-        testDiag("Got NULL, expected \"%s\".\n", expect);
-        pass = 0;
-    }
-    else if (!expect && got) {
-        testDiag("Got \"%s\", expected NULL.\n", got);
-        pass = 0;
-    }
-    else if (expect && got && strcmp(got, expect)) {
-        testDiag("Got \"%s\", expected \"%s\".\n", got, expect);
-        pass = 0;
-    }
-    testOk(pass, "%s", str);
-}
-
-MAIN(macEnvExpandTest)
-{
-    eltc(0);
-    testPlan(71);
-
-    check("FOO", "FOO");
-
-    check("${FOO}", NULL);
-    check("${FOO,BAR}", NULL);
-    check("${FOO,BAR=baz}", NULL);
-    check("${FOO,BAR=$(FOO)}", NULL);
-    check("${FOO,FOO}", NULL);
-    check("${FOO,FOO=$(FOO)}", NULL);
-    check("${FOO,BAR=baz,FUM}", NULL);
-
-    check("${=}", "");
-    check("x${=}y", "xy");
-
-    check("${,=}", "");
-    check("x${,=}y", "xy");
-
-    check("${FOO=}", "");
-    check("x${FOO=}y", "xy");
-
-    check("${FOO=,}", "");
-    check("x${FOO=,}y", "xy");
-
-    check("${FOO,FOO=}", "");
-    check("x${FOO,FOO=}y", "xy");
-
-    check("${FOO=,BAR}", "");
-    check("x${FOO=,BAR}y", "xy");
-
-    check("${FOO=$(BAR=)}", "");
-    check("x${FOO=$(BAR=)}y", "xy");
-
-    check("${FOO=,BAR=baz}", "");
-    check("x${FOO=,BAR=baz}y", "xy");
-
-    check("${FOO=$(BAR),BAR=}", "");
-    check("x${FOO=$(BAR),BAR=}y", "xy");
-
-    check("${=BAR}", "BAR");
-    check("x${=BAR}y", "xBARy");
-
-    check("${FOO=BAR}", "BAR");
-    check("x${FOO=BAR}y", "xBARy");
-
-    epicsEnvSet("FOO","BLETCH");
-    check("${FOO}", "BLETCH");
-    check("${FOO,FOO}", "BLETCH");
-    check("x${FOO}y", "xBLETCHy");
-    check("x${FOO}y${FOO}z", "xBLETCHyBLETCHz");
-    check("${FOO=BAR}", "BLETCH");
-    check("x${FOO=BAR}y", "xBLETCHy");
-    check("${FOO=${BAZ}}", "BLETCH");
-    check("${FOO=${BAZ},BAR=$(BAZ)}", "BLETCH");
-    check("x${FOO=${BAZ}}y", "xBLETCHy");
-    check("x${FOO=${BAZ},BAR=$(BAZ)}y", "xBLETCHy");
-    check("${BAR=${FOO}}", "BLETCH");
-    check("x${BAR=${FOO}}y", "xBLETCHy");
-    check("w${BAR=x${FOO}y}z", "wxBLETCHyz");
-
-    check("${FOO,FOO=BAR}", "BAR");
-    check("x${FOO,FOO=BAR}y", "xBARy");
-    check("${BAR,BAR=$(FOO)}", "BLETCH");
-    check("x${BAR,BAR=$(FOO)}y", "xBLETCHy");
-    check("${BAR,BAR=$($(FOO)),BLETCH=GRIBBLE}", "GRIBBLE");
-    check("x${BAR,BAR=$($(FOO)),BLETCH=GRIBBLE}y", "xGRIBBLEy");
-    check("${$(BAR,BAR=$(FOO)),BLETCH=GRIBBLE}", "GRIBBLE");
-    check("x${$(BAR,BAR=$(FOO)),BLETCH=GRIBBLE}y", "xGRIBBLEy");
-
-    epicsEnvSet("BAR","GLEEP");
-    check("${FOO}/${BAR}", "BLETCH/GLEEP");
-    check("x${FOO}/${BAR}y", "xBLETCH/GLEEPy");
-    check("${FOO,BAR}/${BAR}", "BLETCH/GLEEP");
-    check("${FOO,BAR=x}/${BAR}", "BLETCH/GLEEP");
-    check("${BAZ=BLETCH,BAR}/${BAR}", "BLETCH/GLEEP");
-    check("${BAZ=BLETCH,BAR=x}/${BAR}", "BLETCH/GLEEP");
-
-    epicsEnvSet("BLETCH","BAR");
-    check("${${FOO}}", "BAR");
-    check("x${${FOO}}y", "xBARy");
-    check("${${FOO}=GRIBBLE}", "BAR");
-    check("x${${FOO}=GRIBBLE}y", "xBARy");
-
-    epicsEnvSet("BLETCH","${BAR}");
-    check("${${FOO}}", "GLEEP");
-
-    epicsEnvSet("FOO","${BAR}");
-    check("${FOO}","GLEEP");
-
-    epicsEnvSet("BAR","${BAZ}");
-    check("${FOO}", NULL);
-
-    epicsEnvSet("BAR","${BAZ=GRIBBLE}");
-    check("${FOO}", "GRIBBLE");
-
-    epicsEnvSet("BAR","${STR1}");
-    epicsEnvSet("STR1","VAL1");
-    epicsEnvSet("STR2","VAL2");
-    check("${FOO}", "VAL1");
-
-    epicsEnvSet("BAR","${STR2}");
-    check("${FOO}", "VAL2");
-
-    epicsEnvSet("BAR","${FOO}");
-    check("${FOO}", NULL);
-    check("${FOO,FOO=$(FOO)}", NULL);
-    check("${FOO=$(FOO)}", NULL);
-    check("${FOO=$(BAR),BAR=$(FOO)}", NULL);
-    
-    errlogFlush();
-    eltc(1);
-    return testDone();
-}