Adding interactive mode for unit tests (UT_INTERACTIVE) (#715)

test/common/EnvVars.cpp

@@ -61,6 +61,7 @@ namespace RcclUnitTesting
     printValues    = GetEnvVar("UT_PRINT_VALUES", 0);
     maxRanksPerGpu = GetEnvVar("UT_MAX_RANKS_PER_GPU", 1);
     showTiming     = GetEnvVar("UT_SHOW_TIMING",  1);
+    useInteractive = GetEnvVar("UT_INTERACTIVE",  0);
 
     // Limit number of supported reduction operators to just ncclSum if only allReduce is built
 #ifdef BUILD_ALLREDUCE_ONLY
@@ -170,7 +171,8 @@ namespace RcclUnitTesting
         std::make_pair("UT_DATATYPES"        , "List of datatypes to test"),
         std::make_pair("UT_MAX_RANKS_PER_GPU", "Maximum number of ranks using the same GPU"),
         std::make_pair("UT_PRINT_VALUES"     , "Print array values (# of values to print, < 0 for all)"),
-        std::make_pair("UT_SHOW_TIMING"      , "Show timing table")
+        std::make_pair("UT_SHOW_TIMING"      , "Show timing table"),
+        std::make_pair("UT_INTERACTIVE"      , "Run in interactive mode")
       };
 
     printf("================================================================================\n");