diff --git a/PDP11/pdp11_rp.c b/PDP11/pdp11_rp.c
index afc10545..cb99a766 100644
--- a/PDP11/pdp11_rp.c
+++ b/PDP11/pdp11_rp.c
@@ -1154,8 +1154,7 @@ else { /* Bottom End (After I/O processing) */
         case FNC_SEARCH:                                /* search */
         case FNC_SEEK:                                  /* seek */
         case FNC_WRITEH:                                /* write headers stub */
-            sim_abort ("rp_svc() error", __FILE__, __LINE__); /* should NEVER happen */
-            break;
+            return SCPE_IERR;                           /* should NEVER happen */
 
         case FNC_WRITE:                                 /* write */
         case FNC_WCHK:                                  /* write check */
diff --git a/scp.c b/scp.c
index abcdbc1d..49dd2185 100644
--- a/scp.c
+++ b/scp.c
@@ -12339,7 +12339,7 @@ else
 if (uptr->next) {
     char buf[128];
     snprintf (buf, sizeof (buf), "Cancel failed for %s\n", sim_uname(uptr));
-    sim_abort (buf, __FILE__, __LINE__);
+    SIM_SCP_ABORT (buf);
     }
 return SCPE_OK;
 }
@@ -13707,7 +13707,7 @@ return SCPE_OK;
 
 /* Abort and sanely close output files */
 /* This routine should ONLY be called from SCP modules */
-void sim_abort (const char *msg, const char *file, int linenum)
+void _sim_scp_abort (const char *msg, const char *file, int linenum)
 {
 sim_printf ("%s - aborting from %s:%d\n", msg, file, linenum);
 sim_flush_buffered_files ();
diff --git a/scp.h b/scp.h
index 65c655e7..5af24b39 100644
--- a/scp.h
+++ b/scp.h
@@ -275,7 +275,10 @@ void _sim_debug_device (uint32 dbits, DEVICE* dptr, const char* fmt, ...) GCC_FM
 #define sim_debug_unit(dbits, uptr, ...) do { if ((sim_deb != NULL) && ((uptr) != NULL) && (uptr->dptr != NULL) && (((uptr)->dctrl | (uptr)->dptr->dctrl) & (dbits))) _sim_debug_unit (dbits, uptr, __VA_ARGS__);} while (0)
 #endif
 void sim_flush_buffered_files (void);
-void sim_abort (const char *msg, const char *filename, int filelinenum);
+
+/* Only for use in SCP code and libraries - NOT in simulator code */
+#define SIM_SCP_ABORT(msg) _sim_scp_abort (msg, __FILE__, __LINE__)
+void _sim_scp_abort (const char *msg, const char *filename, int filelinenum);
 
 void fprint_stopped_gen (FILE *st, t_stat v, REG *pc, DEVICE *dptr);
 #define SCP_HELP_FLAT   (1u << 31)       /* Force flat help when prompting is not possible */
diff --git a/sim_defs.h b/sim_defs.h
index 7c4d1c2e..d0fc943f 100644
--- a/sim_defs.h
+++ b/sim_defs.h
@@ -1145,7 +1145,7 @@ struct MEMFILE {
 #define ASSURE(_Expression) while (!(_Expression)) {                                    \
                                 char buf[512];                                          \
                                 snprintf(buf, sizeof (buf), "%s failed", #_Expression); \
-                                sim_abort (buf, __FILE__, __LINE__);                    \
+                                SIM_SCP_ABORT (buf);                                    \
                                 }
 
 /* Asynch/Threaded I/O support */
@@ -1193,8 +1193,7 @@ extern int32 sim_asynch_inst_latency;
             (_cptr != QUEUE_LIST_END);                          \
             _cptr = _cptr->next)                                \
             if (!_cptr->next)                                   \
-                sim_abort ("Queue Corruption detected",         \
-                           __FILE__, __LINE__);                 \
+                SIM_SCP_ABORT ("Queue Corruption detected");    \
         if (lock)                                               \
             pthread_mutex_unlock (lock);                        \
         } while (0)
@@ -1348,8 +1347,7 @@ extern int32 sim_asynch_inst_latency;
 #endif /* USE_AIO_INTRINSICS */
 #define AIO_VALIDATE(uptr)                                             \
     if (!pthread_equal ( pthread_self(), sim_asynch_main_threadid )) { \
-      sim_abort ("Improper thread context for operation detected",     \
-                 __FILE__, __LINE__);                                  \
+      SIM_SCP_ABORT ("Improper thread context for operation detected");\
       } else (void)0
 #define AIO_CHECK_EVENT                                                \
     if (0 > --sim_asynch_check) {                                      \
diff --git a/sim_disk.c b/sim_disk.c
index 22dcbff5..8a46c90a 100644
--- a/sim_disk.c
+++ b/sim_disk.c
@@ -234,7 +234,7 @@ if ((!callback) || !ctx->asynch_io)
                 op, (int)(uptr - ctx->dptr->units), _lba, _sects);\
                                                                 \
         if (ctx->callback)      /* horrible mistake, stop */    \
-            sim_abort ("AIO_CALL error", __FILE__, __LINE__);   \
+            SIM_SCP_ABORT ("AIO_CALL error");                   \
         ctx->io_dop = op;                                       \
         ctx->lba = _lba;                                        \
         ctx->buf = _buf;                                        \
@@ -316,7 +316,7 @@ DISK_PCALLBACK callback = ctx->callback;
 sim_debug_unit (ctx->dbit, uptr, "_disk_completion_dispatch(unit=%d, dop=%d, callback=%p)\n", (int)(uptr - ctx->dptr->units), ctx->io_dop, (void *)(ctx->callback));
 
 if (ctx->io_dop != DOP_DONE)
-    sim_abort ("_disk_completion_dispatch()", __FILE__, __LINE__); /* horribly wrong, stop */
+    SIM_SCP_ABORT ("_disk_completion_dispatch()"); /* horribly wrong, stop */
 
 if (ctx->callback && ctx->io_dop == DOP_DONE) {
     ctx->callback = NULL;
diff --git a/sim_ether.c b/sim_ether.c
index 6f7a53e1..47211099 100644
--- a/sim_ether.c
+++ b/sim_ether.c
@@ -3721,7 +3721,7 @@ switch (dev->eth_api) {
     break;
   default:
     bpf_used = to_me = 0;                           /* Should NEVER happen */
-    sim_abort ("_eth_callback()", __FILE__, __LINE__);
+    SIM_SCP_ABORT ("_eth_callback()");
     break;
   }
 
diff --git a/sim_tape.c b/sim_tape.c
index 6feff983..5580c18f 100644
--- a/sim_tape.c
+++ b/sim_tape.c
@@ -187,7 +187,7 @@ if ((callback == NULL) || !(ctx->asynch_io))
       "sim_tape AIO_CALL(op=%d, unit=%d)\n", op, (int)(uptr-ctx->dptr->units));\
                                                                         \
         if (ctx->callback)      /* horrible mistake, stop */            \
-            sim_abort ("AIO_CALL error", __FILE__, __LINE__);           \
+            SIM_SCP_ABORT ("AIO_CALL error");                           \
         ctx->io_top = op;                                               \
         ctx->buf = _buf;                                                \
         ctx->bc = _bc;                                                  \
@@ -325,7 +325,7 @@ TAPE_PCALLBACK callback = ctx->callback;
 sim_debug_unit (ctx->dbit, uptr, "_tape_completion_dispatch(unit=%d, top=%d, callback=%p)\n", (int)(uptr-ctx->dptr->units), ctx->io_top, ctx->callback);
 
 if (ctx->io_top != TOP_DONE)
-    sim_abort ("_tape_completion_dispatch()", __FILE__, __LINE__); /* horribly wrong, stop */
+    SIM_SCP_ABORT ("_tape_completion_dispatch()"); /* horribly wrong, stop */
 
 if (ctx->asynch_io)
     pthread_mutex_lock (&ctx->io_lock);
diff --git a/sim_tmxr.c b/sim_tmxr.c
index 8370962e..1ee64baa 100644
--- a/sim_tmxr.c
+++ b/sim_tmxr.c
@@ -3898,7 +3898,7 @@ while (sim_asynch_enabled) {
             if (select_errno == EINTR)
                 break;
             sim_printf ("select() returned -1, errno=%d - %s\r\n", select_errno, strerror(select_errno));
-            sim_abort ("", __FILE__, __LINE__);
+            SIM_SCP_ABORT ("");
             break;
         default:
             wait_count = 0;
@@ -4015,7 +4015,7 @@ while (sim_asynch_enabled) {
     switch (status) {
         case WAIT_FAILED:
             sim_printf ("WaitForMultipleObjects() Failed, LastError=%d\r\n", GetLastError());
-            sim_abort ("", __FILE__, __LINE__);
+            SIM_SCP_ABORT ("");
             break;
         case WAIT_TIMEOUT:
             sim_debug (TMXR_DBG_ASY, dptr, "_tmxr_serial_poll() - Poll Timeout - %dms\n", timeout_usec/1000);
@@ -4126,7 +4126,7 @@ while (sim_asynch_enabled) {
                        &iosb, 0, 0, buf, 1, 1, term, 0, 0);
     if (status != SS$_NORMAL) {
         sim_printf ("_tmxr_serial_line_poll() - QIO Failed, Status=%d\r\n", status);
-        sim_abort ("", __FILE__, __LINE__);
+        SIM_SCP_ABORT ("");
         }
     wait_count = 0;
     sys$synch (0, &iosb);