diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index 04efd68..49943fe 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -283,6 +283,8 @@
                     "                  Rotate log every kbytes. Requires -f option\n"
                     "  -n <count>, --rotate-count=<count>\n"
                     "                  Sets max number of rotated logs to <count>, default 4\n"
+                    "  --id=<id>       If the signature id for logging to file changes, then clear\n"
+                    "                  the fileset and continue\n"
                     "  -v <format>, --format=<format>\n"
                     "                  Sets log print format verb and adverbs, where <format> is:\n"
                     "                    brief long process raw tag thread threadtime time\n"
@@ -546,6 +548,7 @@
     unsigned long setLogSize = 0;
     int getPruneList = 0;
     char *setPruneList = NULL;
+    char *setId = NULL;
     int printStatistics = 0;
     int mode = ANDROID_LOG_RDONLY;
     const char *forceFilters = NULL;
@@ -573,6 +576,7 @@
         int option_index = 0;
         // list of long-argument only strings for later comparison
         static const char pid_str[] = "pid";
+        static const char id_str[] = "id";
         static const char wrap_str[] = "wrap";
         static const char print_str[] = "print";
         static const struct option long_options[] = {
@@ -587,6 +591,7 @@
           { "grep",          required_argument, NULL,   'e' },
           // hidden and undocumented reserved alias for --max-count
           { "head",          required_argument, NULL,   'm' },
+          { id_str,          required_argument, NULL,   0 },
           { "last",          no_argument,       NULL,   'L' },
           { "max-count",     required_argument, NULL,   'm' },
           { pid_str,         required_argument, NULL,   0 },
@@ -612,7 +617,7 @@
 
         switch (ret) {
             case 0:
-                // One of the long options
+                // only long options
                 if (long_options[option_index].name == pid_str) {
                     // ToDo: determine runtime PID_MAX?
                     if (!getSizeTArg(optarg, &pid, 1)) {
@@ -643,6 +648,10 @@
                     g_printItAnyways = true;
                     break;
                 }
+                if (long_options[option_index].name == id_str) {
+                    setId = optarg && optarg[0] ? optarg : NULL;
+                    break;
+                }
             break;
 
             case 's':
@@ -967,7 +976,20 @@
         logcat_panic(true, "-r requires -f as well\n");
     }
 
-    setupOutput();
+    if (setId != NULL) {
+        if (g_outputFileName == NULL) {
+            logcat_panic(true, "--id='%s' requires -f as well\n", setId);
+        }
+
+        std::string file_name = android::base::StringPrintf("%s.id", g_outputFileName);
+        std::string file;
+        bool file_ok = android::base::ReadFileToString(file_name, &file);
+        android::base::WriteStringToFile(setId, file_name,
+                                         S_IRUSR | S_IWUSR, getuid(), getgid());
+        if (!file_ok || (file.compare(setId) == 0)) {
+            setId = NULL;
+        }
+    }
 
     if (hasSetLogFormat == 0) {
         const char* logFormat = getenv("ANDROID_PRINTF_LOG");
@@ -1033,7 +1055,7 @@
             continue;
         }
 
-        if (clearLog) {
+        if (clearLog || setId) {
             if (g_outputFileName) {
                 int maxRotationCountDigits =
                     (g_maxRotatedLogs > 0) ? (int) (floor(log10(g_maxRotatedLogs) + 1)) : 0;
@@ -1175,7 +1197,6 @@
         return EXIT_SUCCESS;
     }
 
-
     if (getLogSize) {
         return EXIT_SUCCESS;
     }
@@ -1186,6 +1207,8 @@
         return EXIT_SUCCESS;
     }
 
+    setupOutput(mode);
+
     //LOG_EVENT_INT(10, 12345);
     //LOG_EVENT_LONG(11, 0x1122334455667788LL);
     //LOG_EVENT_STRING(0, "whassup, doc?");
diff --git a/logcat/tests/logcat_test.cpp b/logcat/tests/logcat_test.cpp
index 0043d1b..3daee13 100644
--- a/logcat/tests/logcat_test.cpp
+++ b/logcat/tests/logcat_test.cpp
@@ -20,6 +20,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
@@ -848,6 +849,75 @@
     EXPECT_FALSE(system(command));
 }
 
+static int logrotate_count_id(const char *logcat_cmd, const char *tmp_out_dir) {
+
+    static const char log_filename[] = "log.txt";
+    char command[strlen(tmp_out_dir) + strlen(logcat_cmd) + strlen(log_filename) + 32];
+
+    snprintf(command, sizeof(command), logcat_cmd, tmp_out_dir, log_filename);
+
+    int ret;
+    EXPECT_FALSE((ret = system(command)));
+    if (ret) {
+        return -1;
+    }
+    std::unique_ptr<DIR, decltype(&closedir)> dir(opendir(tmp_out_dir), closedir);
+    EXPECT_NE(nullptr, dir);
+    if (!dir) {
+        return -1;
+    }
+    struct dirent *entry;
+    int count = 0;
+    while ((entry = readdir(dir.get()))) {
+        if (strncmp(entry->d_name, log_filename, sizeof(log_filename) - 1)) {
+            continue;
+        }
+        ++count;
+    }
+    return count;
+}
+
+TEST(logcat, logrotate_id) {
+    static const char logcat_cmd[] = "logcat -b all -d -f %s/%s -n 32 -r 1 --id=test";
+    static const char logcat_short_cmd[] = "logcat -b all -t 10 -f %s/%s -n 32 -r 1 --id=test";
+    static const char tmp_out_dir_form[] = "/data/local/tmp/logcat.logrotate.XXXXXX";
+    static const char log_filename[] = "log.txt";
+    char tmp_out_dir[strlen(tmp_out_dir_form) + 1];
+    ASSERT_TRUE(NULL != mkdtemp(strcpy(tmp_out_dir, tmp_out_dir_form)));
+
+    EXPECT_EQ(34, logrotate_count_id(logcat_cmd, tmp_out_dir));
+    EXPECT_EQ(34, logrotate_count_id(logcat_short_cmd, tmp_out_dir));
+
+    char id_file[strlen(tmp_out_dir_form) + strlen(log_filename) + 5];
+    snprintf(id_file, sizeof(id_file), "%s/%s.id", tmp_out_dir, log_filename);
+    if (getuid() != 0) {
+        chmod(id_file, 0);
+        EXPECT_EQ(34, logrotate_count_id(logcat_short_cmd, tmp_out_dir));
+    }
+    unlink(id_file);
+    EXPECT_EQ(34, logrotate_count_id(logcat_short_cmd, tmp_out_dir));
+
+    FILE *fp = fopen(id_file, "w");
+    if (fp) {
+        fprintf(fp, "not_a_test");
+        fclose(fp);
+    }
+    if (getuid() != 0) {
+        chmod(id_file, 0); // API to preserve content even with signature change
+        ASSERT_EQ(34, logrotate_count_id(logcat_short_cmd, tmp_out_dir));
+        chmod(id_file, 0600);
+    }
+
+    int new_signature;
+    EXPECT_LE(2, (new_signature = logrotate_count_id(logcat_short_cmd, tmp_out_dir)));
+    EXPECT_GT(34, new_signature);
+
+    static const char cleanup_cmd[] = "rm -rf %s";
+    char command[strlen(cleanup_cmd) + strlen(tmp_out_dir_form)];
+    snprintf(command, sizeof(command), cleanup_cmd, tmp_out_dir);
+    EXPECT_FALSE(system(command));
+}
+
 TEST(logcat, logrotate_nodir) {
     // expect logcat to error out on writing content and exit(1) for nodir
     EXPECT_EQ(W_EXITCODE(1, 0),