if ("clear" == Cmd.command) {
						//Clear command is ignored since expired data is cleaned when receiving data tuples
						appTrc(Trace.info, "Clear command received. Nothing cleaned here.", "CustomContext");
					}
					if ("write" == Cmd.command) {
						mutable int32 ferror = -1;
						mutable uint64 fileWriteH = 0; //the write file handle for the checkpoint file
						fileWriteH = spl.file::fopen(checkpointFile, "w", ferror);
						if (0!=ferror) {
							appTrc(Trace.error, "Can not open checkpointFile="+checkpointFile+" ferror="+strerror(ferror), "CustomContext");
							Cmd.success =false;
						} else {
							appTrc(Trace.info, "Open file success checkpointFile="+checkpointFile, "CustomContext");
							spl.file::fwriteBin (subscriberMap, fileWriteH, ferror);
							if (0!=ferror) {
								appTrc(Trace.error, "Can not write checkpointFile="+checkpointFile+" ferror="+strerror(ferror), "CustomContext");
								Cmd.success =false;
							} else {
								if (0!=spl.file::fclose(fileWriteH, ferror)) {
									appTrc(Trace.error, "On fclose file: " + checkpointFile + " ferror="+strerror(ferror), "CustomContext");
								}
								else {
									argument = checkpointFile; // for statistic log file only to indicate that file was written

									// save metrics
									fileWriteH = spl.file::fopen(metricsFile, "w", ferror);
									if (0!=ferror) {
										appTrc(Trace.error, "Can not open metricsFile="+metricsFile+" ferror="+strerror(ferror), "CustomContext");
										Cmd.success =false;
									} else {
										appTrc(Trace.info, "Open file success metricsFile="+metricsFile, "CustomContext");
										spl.file::fwriteBin (metrics, fileWriteH, ferror);
										if (0!=ferror) {
											appTrc(Trace.error, "Can not write metricsFile="+metricsFile+" ferror="+strerror(ferror), "CustomContext");
											Cmd.success =false;
										} else {
											if (0!=spl.file::fclose(fileWriteH, ferror)) {
												appTrc(Trace.error, "On fclose file: " + metricsFile + " ferror="+strerror(ferror), "CustomContext");
											}
										}
									}
								}
							}
						}
					}
					if ("read" == Cmd.command) {
						mutable int32 ferror = -1;
						mutable uint64 fileReadH = 0; //the read file handle for the checkpoint file
						fileReadH = spl.file::fopen(checkpointFile, "r", ferror);
						if (0!=ferror) {
							appTrc(Trace.error, "Can not open checkpointFile="+checkpointFile+" ferror="+strerror(ferror), "CustomContext");
							Cmd.success =false;
						} else {
							appTrc(Trace.info, "Open file success checkpointFile="+checkpointFile, "CustomContext");
							spl.file::freadBin (subscriberMap, fileReadH, ferror);
							if (0!=ferror) {
								appTrc(Trace.error, "Can not read checkpointFile="+checkpointFile+" ferror="+strerror(ferror), "CustomContext");
								Cmd.success =false;
							} else {
								if (0!=spl.file::fclose(fileReadH, ferror)) {
									appTrc(Trace.error, "On fclose file: " + checkpointFile + " ferror="+strerror(ferror), "CustomContext");
								}
								else {
									argument = checkpointFile; // for statistic log file only to indicate that file was written

									// restore metrics
									fileReadH = spl.file::fopen(metricsFile, "r", ferror);
									if (0!=ferror) {
										appTrc(Trace.error, "Can not open metricsFile="+metricsFile+" ferror="+strerror(ferror), "CustomContext");
										Cmd.success =false;
									} else {
										appTrc(Trace.info, "Open file success metricsFile="+metricsFile, "CustomContext");
										spl.file::freadBin (metrics, fileReadH, ferror);
										if (0!=ferror) {
											appTrc(Trace.error, "Can not read metricsFile="+metricsFile+" ferror="+strerror(ferror), "CustomContext");
											Cmd.success =false;
										} else {
											if (0!=spl.file::fclose(fileReadH, ferror)) {
												appTrc(Trace.error, "On fclose file: " + metricsFile + " ferror="+strerror(ferror), "CustomContext");
											} else {
												submit(metrics, CampaignMetricsStream);
												spl.file::remove(metricsFile, ferror);
											}
										}
									}
								}
							}
						}
					}