diff --git a/scp.c b/scp.c
index 2de6f248..0cda26d6 100644
--- a/scp.c
+++ b/scp.c
@@ -2123,7 +2123,7 @@ else if (*argv[0]) {                                    /* sim name arg? */
     strncpy (nbuf + 1, argv[0], PATH_MAX + 1);          /* copy sim name */
     if ((np = (char *)match_ext (nbuf, "EXE")))         /* remove .exe */
         *np = 0;
-    sim_strlcat (nbuf, ".ini\"", sizeof(nbuf));         /* add .ini" */
+    strlcat (nbuf, ".ini\"", sizeof(nbuf));         /* add .ini" */
     stat = do_cmd (-1, nbuf) & ~SCPE_NOMESSAGE;         /* proc default cmd file */
     if (stat == SCPE_OPENERR) {                         /* didn't exist/can't open? */
         np = strrchr (nbuf, '/');                       /* stript path and try again in cwd */
@@ -2916,8 +2916,8 @@ for (nargs = 0; nargs < 10; ) {                         /* extract arguments */
 if (do_arg [0] == NULL)                                 /* need at least 1 */
     return SCPE_2FARG;
 if ((fpin = fopen (do_arg[0], "r")) == NULL) {          /* file failed to open? */
-    sim_strlcpy (cbuf, do_arg[0], sizeof (cbuf));       /* try again with .sim extension */
-    sim_strlcat (cbuf, ".sim", sizeof (cbuf));
+    strlcpy (cbuf, do_arg[0], sizeof (cbuf));           /* try again with .sim extension */
+    strlcat (cbuf, ".sim", sizeof (cbuf));
     if ((fpin = fopen (cbuf, "r")) == NULL) {           /* failed a second time? */
         if (flag == 0)                                  /* cmd line file? */
              fprintf (stderr, "Can't open file %s\n", do_arg[0]);
@@ -5094,15 +5094,15 @@ sim_strlcpy (WildName, cptr, sizeof(WildName));
 cptr = WildName;
 sim_trim_endspc (WildName);
 if ((!stat (WildName, &filestat)) && (filestat.st_mode & S_IFDIR))
-    sim_strlcat (WildName, "/*", sizeof(WildName));
+    strlcat (WildName, "/*", sizeof(WildName));
 if ((*cptr != '/') || (0 == memcmp (cptr, "./", 2)) || (0 == memcmp (cptr, "../", 3))) {
 #if defined (VMS)
     getcwd (WholeName, sizeof(WholeName)-1, 0);
 #else
     getcwd (WholeName, sizeof(WholeName)-1);
 #endif
-    sim_strlcat (WholeName, "/", sizeof(WholeName));
-    sim_strlcat (WholeName, cptr, sizeof(WholeName));
+    strlcat (WholeName, "/", sizeof(WholeName));
+    strlcat (WholeName, cptr, sizeof(WholeName));
     sim_trim_endspc (WholeName);
     }
 else
diff --git a/scp.h b/scp.h
index f8301cb0..0b3228cb 100644
--- a/scp.h
+++ b/scp.h
@@ -160,6 +160,10 @@ int sim_strncasecmp (const char *string1, const char *string2, size_t len);
 int sim_strcasecmp (const char *string1, const char *string2);
 size_t sim_strlcat (char *dst, const char *src, size_t size);
 size_t sim_strlcpy (char *dst, const char *src, size_t size);
+#define strlcpy(dst, src, size) sim_strlcpy((dst), (src), (size))
+#define strlcat(dst, src, size) sim_strlcat((dst), (src), (size))
+#define strncasecmp(str1, str2, len) sim_strncasecmp((str1), (str2), (len))
+#define strcasecmp(str1, str2) sim_strcasecmp ((str1), (str2))
 CONST char *get_sim_opt (int32 opt, CONST char *cptr, t_stat *st);
 const char *put_switches (char *buf, size_t bufsize, uint32 sw);
 CONST char *get_glyph (const char *iptr, char *optr, char mchar);
diff --git a/sim_console.c b/sim_console.c
index d87b1101..5bb132a4 100644
--- a/sim_console.c
+++ b/sim_console.c
@@ -861,7 +861,7 @@ CONST char *cptr;
 int32 saved_switches = sim_switches;
 t_stat stat;
 
-sim_strlcpy (cbuf, sim_rem_command_buf, sizeof (cbuf));
+strlcpy (cbuf, sim_rem_command_buf, sizeof (cbuf));
 while (isspace(cbuf[0]))
     memmove (cbuf, cbuf+1, strlen(cbuf+1)+1);   /* skip leading whitespace */
 sim_sub_args (cbuf, sizeof(cbuf), argv);
@@ -3598,8 +3598,8 @@ static t_stat sim_os_ttinit (void) {
     SIOUXSettings.toppixel = 42;
     SIOUXSettings.leftpixel     = 6;
     iBeamCursorH = GetCursor(iBeamCursor);
-    sim_strlcat(title, sim_name, sizeof(title));
-    sim_strlcat(title, " Simulator", sizeof(title));
+    strlcat(title, sim_name, sizeof(title));
+    strlcat(title, " Simulator", sizeof(title));
     title[0] = strlen(title) - 1;                       /* Pascal string done */
     for (i = 0; i <= title[0]; i++) {                   /* copy to unsigned char */
         ptitle[i] = title[i];
diff --git a/sim_ether.c b/sim_ether.c
index 761a8de5..47cf9780 100644
--- a/sim_ether.c
+++ b/sim_ether.c
@@ -1144,7 +1144,7 @@ int load_pcap(void) {
           char npcap_path[512] = "";
 
           if (p_GetSystemDirectory (npcap_path, sizeof(npcap_path) - 7))
-            sim_strlcat (npcap_path, "\\Npcap", sizeof(npcap_path));
+            strlcat (npcap_path, "\\Npcap", sizeof(npcap_path));
           if (p_SetDllDirectory(npcap_path))
             hLib = LoadLibraryA(lib_name);
           p_SetDllDirectory (NULL);