diff --git a/darshan-runtime/lib/darshan-posix.c b/darshan-runtime/lib/darshan-posix.c
index c62d7141044e25fbf873504cdea9010ccd11e4ec..1d1f1c060dfc5a36b89bf27b397ae2c58829818b 100644
--- a/darshan-runtime/lib/darshan-posix.c
+++ b/darshan-runtime/lib/darshan-posix.c
@@ -46,6 +46,7 @@ DARSHAN_FORWARD_DECL(creat64, int, (const char* path, mode_t mode));
 DARSHAN_FORWARD_DECL(dup, int, (int oldfd));
 DARSHAN_FORWARD_DECL(dup2, int, (int oldfd, int newfd));
 DARSHAN_FORWARD_DECL(dup3, int, (int oldfd, int newfd, int flags));
+DARSHAN_FORWARD_DECL(fileno, int, (FILE *stream));
 DARSHAN_FORWARD_DECL(mkstemp, int, (char *template));
 DARSHAN_FORWARD_DECL(mkostemp, int, (char *template, int flags));
 DARSHAN_FORWARD_DECL(mkstemps, int, (char *template, int suffixlen));
@@ -169,9 +170,8 @@ extern void dxt_posix_write(darshan_record_id rec_id, int64_t offset,
 extern void dxt_posix_read(darshan_record_id rec_id, int64_t offset,
     int64_t length, double start_time, double end_time);
 
-/* function for registering a newly opened file descriptor with the POSIX module */
-int darshan_posix_add_open_fd(int fd, char *rec_name, int counter,
-    double tm1, double tm2);
+/* extern function def for querying record name from a STDIO stream */
+extern char *darshan_stdio_lookup_record_name(FILE *stream);
 
 static struct posix_runtime *posix_runtime = NULL;
 static pthread_mutex_t posix_runtime_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
@@ -581,6 +581,38 @@ int DARSHAN_DECL(dup3)(int oldfd, int newfd, int flags)
     return(ret);
 }
 
+int DARSHAN_DECL(fileno)(FILE *stream)
+{
+    int ret;
+    double tm1, tm2;
+    darshan_record_id rec_id;
+    struct posix_file_record_ref *rec_ref;
+
+    MAP_OR_FAIL(fileno);
+
+    tm1 = darshan_core_wtime();
+    ret = __real_fileno(stream);
+    tm2 = darshan_core_wtime();
+
+    if(ret >= 0)
+    {
+        char *rec_name = darshan_stdio_lookup_record_name(stream);
+        if(rec_name)
+        {
+            POSIX_PRE_RECORD();
+            rec_id = darshan_core_gen_record_id(rec_name);
+            rec_ref = darshan_lookup_record_ref(posix_runtime->rec_id_hash,
+                &rec_id, sizeof(darshan_record_id));
+            if(!rec_ref)
+                rec_ref = posix_track_new_file_record(rec_id, rec_name);
+            POSIX_RECORD_REFOPEN(ret, rec_ref, tm1, tm2, POSIX_FILENOS);
+            POSIX_POST_RECORD();
+        }
+    }
+
+    return(ret);
+}
+
 int DARSHAN_DECL(mkstemp)(char* template)
 {
     int ret;
@@ -1516,26 +1548,6 @@ static void posix_aio_tracker_add(int fd, void *aiocbp)
     return;
 }
 
-int darshan_posix_add_open_fd(int fd, char *rec_name, int counter,
-    double tm1, double tm2)
-{
-    darshan_record_id rec_id;
-    struct posix_file_record_ref *rec_ref;
-    int ret = 0;
-
-    POSIX_PRE_RECORD();
-    rec_id = darshan_core_gen_record_id(rec_name);
-    rec_ref = darshan_lookup_record_ref(posix_runtime->rec_id_hash, &rec_id,
-        sizeof(darshan_record_id));
-    if(!rec_ref)
-        rec_ref = posix_track_new_file_record(rec_id, rec_name);
-
-    POSIX_RECORD_REFOPEN(fd, rec_ref, tm1, tm2, counter);
-    POSIX_POST_RECORD();
-
-    return(ret);
-}
-
 static void posix_finalize_file_records(void *rec_ref_p)
 {
     struct posix_file_record_ref *rec_ref =
diff --git a/darshan-runtime/lib/darshan-stdio.c b/darshan-runtime/lib/darshan-stdio.c
index 4384db90ea2eb7f57b2355833b76aae9b47f68aa..8a9f977d347c66edd611b2db65d9415713e714c2 100644
--- a/darshan-runtime/lib/darshan-stdio.c
+++ b/darshan-runtime/lib/darshan-stdio.c
@@ -118,7 +118,6 @@ DARSHAN_FORWARD_DECL(fseeko64, int, (FILE *stream, off64_t offset, int whence));
 DARSHAN_FORWARD_DECL(fsetpos, int, (FILE *stream, const fpos_t *pos));
 DARSHAN_FORWARD_DECL(fsetpos64, int, (FILE *stream, const fpos64_t *pos));
 DARSHAN_FORWARD_DECL(rewind, void, (FILE *stream));
-DARSHAN_FORWARD_DECL(fileno, int, (FILE *stream));
 
 /* structure to track stdio stats at runtime */
 struct stdio_file_record_ref
@@ -163,11 +162,12 @@ static struct stdio_file_record_ref *stdio_track_new_file_record(
     darshan_record_id rec_id, const char *path);
 static void stdio_cleanup_runtime();
 
-/* external prototype from POSIX module used to register new POSIX file
- * records corresponding to file descriptors returned by STDIO fileno()
- */
-extern int darshan_posix_add_open_fd(int fd, char *rec_name, int counter,
-    double tm1, double tm2);
+/* we need access to fileno (defined in POSIX module) for instrumenting fopen calls */
+#ifdef DARSHAN_PRELOAD
+extern int (*__real_fileno)(FILE *stream);
+#else
+extern int __real_fileno(FILE *stream);
+#endif
 
 #define STDIO_LOCK() pthread_mutex_lock(&stdio_runtime_mutex)
 #define STDIO_UNLOCK() pthread_mutex_unlock(&stdio_runtime_mutex)
@@ -957,35 +957,6 @@ int DARSHAN_DECL(fsetpos64)(FILE *stream, const fpos64_t *pos)
     return(ret);
 }
 
-int DARSHAN_DECL(fileno)(FILE *stream)
-{
-    int ret;
-    struct stdio_file_record_ref *rec_ref;
-    double tm1, tm2;
-
-    MAP_OR_FAIL(fileno);
-
-    tm1 = darshan_core_wtime();
-    ret = __real_fileno(stream);
-    tm2 = darshan_core_wtime();
-
-    if(ret >= 0)
-    {
-        STDIO_PRE_RECORD();
-        rec_ref = darshan_lookup_record_ref(stdio_runtime->stream_hash, &stream, sizeof(stream));
-        if(rec_ref)
-        {
-            char *rec_name = darshan_core_lookup_record_name(
-                rec_ref->file_rec->base_rec.id);
-            /* register this new FD with the POSIX module so we can track it */
-            darshan_posix_add_open_fd(ret, rec_name, POSIX_FILENOS, tm1, tm2);
-        }
-        STDIO_POST_RECORD();
-    }
-
-    return(ret);
-}
-
 /**********************************************************
  * Internal functions for manipulating STDIO module state *
  **********************************************************/
@@ -1442,6 +1413,23 @@ static void stdio_shared_record_variance(MPI_Comm mod_comm,
     return;
 }
 
+char *darshan_stdio_lookup_record_name(FILE *stream)
+{
+    struct stdio_file_record_ref *rec_ref;
+    char *rec_name = NULL;
+
+    STDIO_LOCK();
+    if(stdio_runtime)
+    {
+        rec_ref = darshan_lookup_record_ref(stdio_runtime->stream_hash,
+            &stream, sizeof(stream));
+        if(rec_ref)
+            rec_name = darshan_core_lookup_record_name(rec_ref->file_rec->base_rec.id);
+    }
+    STDIO_UNLOCK();
+
+    return(rec_name);
+}
 
 /*
  * Local variables: