diff --git a/src/posix/platform/daemon.cpp b/src/posix/platform/daemon.cpp
index 5109793c4..297093d47 100644
--- a/src/posix/platform/daemon.cpp
+++ b/src/posix/platform/daemon.cpp
@@ -49,11 +49,26 @@
 static_assert(sizeof(OPENTHREAD_POSIX_DAEMON_SOCKET_NAME) < sizeof(sockaddr_un::sun_path),
               "OpenThread daemon socket name too long!");
 
-static int sListenSocket  = -1;
-static int sDaemonLock    = -1;
-static int sSessionSocket = -1;
+namespace {
 
-static int OutputFormatV(void *aContext, const char *aFormat, va_list aArguments)
+int sListenSocket  = -1;
+int sDaemonLock    = -1;
+int sSessionSocket = -1;
+
+typedef char(Filename)[sizeof(sockaddr_un::sun_path)];
+
+void GetFilename(Filename &aFilename, const char *aPattern)
+{
+    int rval;
+
+    rval = snprintf(aFilename, sizeof(aFilename), aPattern, gNetifName);
+    if (rval < 0 && static_cast<size_t>(rval) >= sizeof(aFilename))
+    {
+        DieNow(OT_EXIT_INVALID_ARGUMENTS);
+    }
+}
+
+int OutputFormatV(void *aContext, const char *aFormat, va_list aArguments)
 {
     OT_UNUSED_VARIABLE(aContext);
 
@@ -86,7 +101,7 @@ exit:
     return rval;
 }
 
-static void InitializeSessionSocket(void)
+void InitializeSessionSocket(void)
 {
     int newSessionSocket;
     int rval;
@@ -133,6 +148,8 @@ exit:
     }
 }
 
+} // namespace
+
 void platformDaemonEnable(otInstance *aInstance)
 {
     struct sockaddr_un sockname;
@@ -151,13 +168,10 @@ void platformDaemonEnable(otInstance *aInstance)
     {
         static_assert(sizeof(OPENTHREAD_POSIX_DAEMON_SOCKET_LOCK) == sizeof(OPENTHREAD_POSIX_DAEMON_SOCKET_NAME),
                       "sock and lock file name pattern should have the same length!");
-        char lockfile[sizeof(sockname.sun_path)];
+        Filename lockfile;
+
+        GetFilename(lockfile, OPENTHREAD_POSIX_DAEMON_SOCKET_LOCK);
 
-        ret = snprintf(lockfile, sizeof(lockfile), OPENTHREAD_POSIX_DAEMON_SOCKET_LOCK, gNetifName);
-        if (ret < 0 && static_cast<size_t>(ret) >= sizeof(lockfile))
-        {
-            DieNowWithMessage("lockfile", OT_EXIT_INVALID_ARGUMENTS);
-        }
         sDaemonLock = open(lockfile, O_CREAT | O_RDONLY | O_CLOEXEC, 0600);
     }
 
@@ -174,11 +188,7 @@ void platformDaemonEnable(otInstance *aInstance)
     memset(&sockname, 0, sizeof(struct sockaddr_un));
 
     sockname.sun_family = AF_UNIX;
-    ret = snprintf(sockname.sun_path, sizeof(sockname.sun_path), OPENTHREAD_POSIX_DAEMON_SOCKET_NAME, gNetifName);
-    if (ret < 0 && static_cast<size_t>(ret) >= sizeof(sockname.sun_path))
-    {
-        DieNowWithMessage("sockfile", OT_EXIT_INVALID_ARGUMENTS);
-    }
+    GetFilename(sockname.sun_path, OPENTHREAD_POSIX_DAEMON_SOCKET_NAME);
     (void)unlink(sockname.sun_path);
 
     ret = bind(sListenSocket, (const struct sockaddr *)&sockname, sizeof(struct sockaddr_un));
@@ -219,8 +229,11 @@ void platformDaemonDisable(void)
 
     if (gPlatResetReason != OT_PLAT_RESET_REASON_SOFTWARE)
     {
-        otLogDebgPlat("Removing daemon socket: %s", OPENTHREAD_POSIX_DAEMON_SOCKET_NAME);
-        (void)unlink(OPENTHREAD_POSIX_DAEMON_SOCKET_NAME);
+        Filename sockfile;
+
+        GetFilename(sockfile, OPENTHREAD_POSIX_DAEMON_SOCKET_NAME);
+        otLogDebgPlat("Removing daemon socket: %s", sockfile);
+        (void)unlink(sockfile);
     }
 
     if (sDaemonLock != -1)