Make VMS CRTL features work for embedders.

The various run-time features of the CRTL that Perl uses were being
fetched at image activation time and stored in static variables
for later reference.  That works ok when Perl is the program, but
not when Perl is the library since in the latter case attempts by
an embedder to alter the feature settings before invoking Perl were
being ignored.

So store the feature index, not its value, and use that index to
get the current value via decc$feature_get_value whenever we need
it.  This means function calls rather than data references, but
there is no measurable impact on performance.

Also fix a bug in the handling of the feature to disable the POSIX
root; we were saying we were disabling it but weren't really doing
so because its current value cannot be set for some reason (only
its default value).  Since the feature only affects the conversion
of filenames between Unix and VMS format and we don't use the CRTL's
functions for that, it's unlikely this bug ever caused trouble.

1 files changed, 145 insertions, 186 deletions

diff --git a/vms/vms.c b/vms/vms.c
index 7698fac6ed..447b5263d1 100644
--- a/vms/vms.c
+++ b/vms/vms.c
@@ -213,19 +213,38 @@ static bool will_taint = FALSE;  /* tainting active, but no PL_curinterp yet */
 /* munching */ 
 static int no_translate_barewords;
 
-/* DECC Features that may need to affect how Perl interprets
- * displays filename information
+/* DECC feature indexes.  We grab the indexes at start-up
+ * time for later use with decc$feature_get_value.
  */
-static int decc_disable_to_vms_logname_translation = 1;
-static int decc_disable_posix_root = 1;
-int decc_efs_case_preserve = 0;
-static int decc_efs_charset = 0;
-static int decc_efs_charset_index = -1;
-static int decc_filename_unix_no_version = 0;
-static int decc_filename_unix_only = 0;
-int decc_filename_unix_report = 0;
-int decc_posix_compliant_pathnames = 0;
-int decc_readdir_dropdotnotype = 0;
+static int disable_to_vms_logname_translation_index = -1;
+static int disable_posix_root_index = -1;
+static int efs_case_preserve_index = -1;
+static int efs_charset_index = -1;
+static int filename_unix_no_version_index = -1;
+static int filename_unix_only_index = -1;
+static int filename_unix_report_index = -1;
+static int posix_compliant_pathnames_index = -1;
+static int readdir_dropdotnotype_index = -1;
+
+#define DECC_DISABLE_TO_VMS_LOGNAME_TRANSLATION \
+    (decc$feature_get_value(disable_to_vms_logname_translation_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_DISABLE_POSIX_ROOT  \
+    (decc$feature_get_value(disable_posix_root_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_EFS_CASE_PRESERVE  \
+    (decc$feature_get_value(efs_case_preserve_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_EFS_CHARSET  \
+    (decc$feature_get_value(efs_charset_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_FILENAME_UNIX_NO_VERSION  \
+    (decc$feature_get_value(filename_unix_no_version_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_FILENAME_UNIX_ONLY  \
+    (decc$feature_get_value(filename_unix_only_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_FILENAME_UNIX_REPORT  \
+    (decc$feature_get_value(filename_unix_report_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_POSIX_COMPLIANT_PATHNAMES   \
+    (decc$feature_get_value(posix_compliant_pathnames_index,__FEATURE_MODE_CURVAL)>0)
+#define DECC_READDIR_DROPDOTNOTYPE  \
+    (decc$feature_get_value(readdir_dropdotnotype_index,__FEATURE_MODE_CURVAL)>0)
+
 static int vms_process_case_tolerant = 1;
 int vms_vtf7_filenames = 0;
 int gnv_unix_shell = 0;
@@ -292,7 +311,7 @@ is_unix_filespec(const char *path)
 	else {
 
 	    /* If the user wants UNIX files, "." needs to be treated as in UNIX */
-	    if (decc_filename_unix_report || decc_filename_unix_only) {
+	    if (DECC_FILENAME_UNIX_REPORT || DECC_FILENAME_UNIX_ONLY) {
 	      if (strEQ(path,"."))
 		ret_val = 1;
 	    }
@@ -475,7 +494,7 @@ copy_expand_unix_filename_escape(char *outspec, const char *inspec, int *output_
 	return 1;
 	break;
     case '?':
-	if (decc_efs_charset == 0)
+	if (DECC_EFS_CHARSET)
 	  outspec[0] = '%';
 	else
 	  outspec[0] = '?';
@@ -751,7 +770,7 @@ vms_split_path(const char * path, char * * volume, int * vol_len, char * * root,
      * The parser can not tell the difference when a "." is a version
      * delimiter or a part of the file specification.
      */
-    if ((decc_efs_charset) && 
+    if ((DECC_EFS_CHARSET) &&
 	(item_list[verspec].length > 0) &&
 	(item_list[verspec].component[0] == '.')) {
 	*name = item_list[namespec].component;
@@ -2143,7 +2162,7 @@ my_tmpfile(void)
   cp = (char *)PerlMem_malloc(L_tmpnam+24);
   if (cp == NULL) _ckvmssts_noperl(SS$_INSFMEM);
 
-  if (decc_filename_unix_only == 0)
+  if (DECC_FILENAME_UNIX_ONLY == 0)
     strcpy(cp,"Sys$Scratch:");
   else
     strcpy(cp,"/tmp/");
@@ -3821,7 +3840,7 @@ vmspipe_tempfile(pTHX)
     */
 
     index++;
-    if (!decc_filename_unix_only) {
+    if (!DECC_FILENAME_UNIX_ONLY) {
       sprintf(file,"sys$scratch:perlpipe_%08.8x_%d.com",mypid,index);
       fp = fopen(file,"w");
       if (!fp) {
@@ -3876,7 +3895,7 @@ vmspipe_tempfile(pTHX)
     fstat(fileno(fp), &s0.crtl_stat);
     fclose(fp);
 
-    if (decc_filename_unix_only)
+    if (DECC_FILENAME_UNIX_ONLY)
 	int_tounixspec(file, file, NULL);
     fp = fopen(file,"r","shr=get");
     if (!fp) return 0;
@@ -5573,7 +5592,7 @@ int_rmsexpand
    rms_set_rsal(mynam, outbuf, NAM$C_MAXRSS, outbufl, (VMS_MAXRSS - 1));
 
 #ifdef NAM$M_NO_SHORT_UPCASE
-  if (decc_efs_case_preserve)
+  if (DECC_EFS_CASE_PRESERVE)
     rms_set_nam_nop(mynam, NAM$M_NO_SHORT_UPCASE);
 #endif
 
@@ -5637,7 +5656,7 @@ int_rmsexpand
   /* If the input filespec contained any lowercase characters,
    * downcase the result for compatibility with Unix-minded code. */
 int_expanded:
-  if (!decc_efs_case_preserve) {
+  if (!DECC_EFS_CASE_PRESERVE) {
     char * tbuf;
     for (tbuf = rms_get_fna(myfab, mynam); *tbuf; tbuf++)
       if (islower(*tbuf)) { haslower = 1; break; }
@@ -5710,7 +5729,7 @@ int_expanded:
 	rms_clear_nam_nop(defnam);
 	rms_set_nam_nop(defnam, NAM$M_SYNCHK);
 #ifdef NAM$M_NO_SHORT_UPCASE
-	if (decc_efs_case_preserve)
+	if (DECC_EFS_CASE_PRESERVE)
 	  rms_set_nam_nop(defnam, NAM$M_NO_SHORT_UPCASE);
 #endif
 #ifdef NAML$M_OPEN_SPECIAL
@@ -5790,7 +5809,7 @@ int_expanded:
 
   /* Posix format specifications must have matching quotes */
   if (speclen < (VMS_MAXRSS - 1)) {
-    if (decc_posix_compliant_pathnames && (spec_buf[0] == '\"')) {
+    if (DECC_POSIX_COMPLIANT_PATHNAMES && (spec_buf[0] == '\"')) {
       if ((speclen > 1) && (spec_buf[speclen-1] != '\"')) {
         spec_buf[speclen] = '\"';
         speclen++;
@@ -5798,7 +5817,7 @@ int_expanded:
     }
   }
   spec_buf[speclen] = '\0';
-  if (haslower && !decc_efs_case_preserve) __mystrtolower(spec_buf);
+  if (haslower && !DECC_EFS_CASE_PRESERVE) __mystrtolower(spec_buf);
 
   /* Have we been working with an expanded, but not resultant, spec? */
   /* Also, convert back to Unix syntax if necessary. */
@@ -6009,7 +6028,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
     dirlen = strlen(dir);
     while (dirlen && dir[dirlen-1] == '/') --dirlen;
     if (!dirlen) { /* We had Unixish '/' -- substitute top of current tree */
-      if (!decc_posix_compliant_pathnames && decc_disable_posix_root) {
+      if (!DECC_POSIX_COMPLIANT_PATHNAMES && DECC_DISABLE_POSIX_ROOT) {
         dir = "/sys$disk";
         dirlen = 9;
       }
@@ -6023,7 +6042,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
     trndir = (char *)PerlMem_malloc(VMS_MAXRSS + 1);
     if (trndir == NULL) _ckvmssts_noperl(SS$_INSFMEM);
     if (!strpbrk(dir+1,"/]>:")  &&
-	(!decc_posix_compliant_pathnames && decc_disable_posix_root)) {
+	(!DECC_POSIX_COMPLIANT_PATHNAMES && DECC_DISABLE_POSIX_ROOT)) {
       strcpy(trndir,*dir == '/' ? dir + 1: dir);
       trnlnm_iter_count = 0;
       while (!strpbrk(trndir,"/]>:") && simple_trnlnm(trndir,trndir,VMS_MAXRSS-1)) {
@@ -6185,7 +6204,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
             }
             is_dir = is_dir_ext(cp2, e_len, cp3, vs_len);
             if (!is_dir) {
-                if (!decc_efs_charset) {
+                if (!DECC_EFS_CHARSET) {
                     /* If this is not EFS, then not a directory */
                     PerlMem_free(trndir);
                     PerlMem_free(vmsdir);
@@ -6201,7 +6220,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
                 /* The .dir for now, and fix this better later */
                 dirlen = cp2 - trndir;
             }
-            if (decc_efs_charset && !strchr(trndir,'/')) {
+            if (DECC_EFS_CHARSET && !strchr(trndir,'/')) {
                 /* Dots are allowed in dir names, so escape them if input not in Unix syntax. */
                 char *cp4 = is_dir ? (cp2 - 1) : cp2;
                   
@@ -6225,11 +6244,11 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
 
       /* We've picked up everything up to the directory file name.
          Now just add the type and version, and we're set. */
-      if ((!decc_efs_case_preserve) && vms_process_case_tolerant)
+      if ((!DECC_EFS_CASE_PRESERVE) && vms_process_case_tolerant)
           strcat(buf,".dir");
       else
           strcat(buf,".DIR");
-      if (!decc_filename_unix_no_version)
+      if (!DECC_FILENAME_UNIX_NO_VERSION)
           strcat(buf,";1");
       PerlMem_free(trndir);
       PerlMem_free(vmsdir);
@@ -6257,7 +6276,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
       rms_set_dna(dirfab, dirnam, ".DIR;1", 6);
       rms_set_esal(dirnam, esa, NAM$C_MAXRSS, esal, (VMS_MAXRSS - 1));
 #ifdef NAM$M_NO_SHORT_UPCASE
-      if (decc_efs_case_preserve)
+      if (DECC_EFS_CASE_PRESERVE)
 	rms_set_nam_nop(dirnam, NAM$M_NO_SHORT_UPCASE);
 #endif
 
@@ -6400,7 +6419,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
           /* Go back and expand rooted logical name */
           rms_set_nam_nop(dirnam, NAM$M_SYNCHK | NAM$M_NOCONCEAL);
 #ifdef NAM$M_NO_SHORT_UPCASE
-	  if (decc_efs_case_preserve)
+	  if (DECC_EFS_CASE_PRESERVE)
 	    rms_set_nam_nop(dirnam, NAM$M_NO_SHORT_UPCASE);
 #endif
           if (!(sys$parse(&dirfab) & STS$K_SUCCESS)) {
@@ -6483,7 +6502,7 @@ int_fileify_dirspec(const char *dir, char *buf, int *utf8_fl)
 
       /* $PARSE may have upcased filespec, so convert output to lower
        * case if input contained any lowercase characters. */
-      if (haslower && !decc_efs_case_preserve) __mystrtolower(buf);
+      if (haslower && !DECC_EFS_CASE_PRESERVE) __mystrtolower(buf);
       PerlMem_free(trndir);
       PerlMem_free(esa);
       if (esal != NULL)
@@ -6602,7 +6621,7 @@ int_pathify_dirspec_simple(const char * dir, char * buf,
             memcpy(&buf[len], n_spec, n_len);
             len += n_len;
             if (e_len > 0) {
-                if (decc_efs_charset) {
+                if (DECC_EFS_CHARSET) {
                     if (e_len == 4 
                         && (toUPPER_A(e_spec[1]) == 'D')
                         && (toUPPER_A(e_spec[2]) == 'I')
@@ -6711,7 +6730,7 @@ int_pathify_dirspec(const char *dir, char *buf)
 
     /* At this point we do not work with *dir, but the copy in  *trndir */
 
-    if (need_to_lower && !decc_efs_case_preserve) {
+    if (need_to_lower && !DECC_EFS_CASE_PRESERVE) {
         /* Legacy mode, lower case the returned value */
         __mystrtolower(trndir);
     }
@@ -6744,7 +6763,7 @@ int_pathify_dirspec(const char *dir, char *buf)
                 /* is a relative Unix directory specification */
 
                 sts = 1;
-                if (!decc_filename_unix_report && decc_efs_charset) {
+                if (!DECC_FILENAME_UNIX_REPORT && DECC_EFS_CHARSET) {
                     int is_dir;
                     is_dir = is_dir_ext(e_spec, e_len, vs_spec, vs_len);
 
@@ -6801,7 +6820,7 @@ int_pathify_dirspec(const char *dir, char *buf)
                     d_spec, d_len, n_spec, n_len,
                     e_spec, e_len, vs_spec, vs_len);
 
-                if ((ret_spec != NULL) && (!decc_efs_case_preserve)) {
+                if ((ret_spec != NULL) && (!DECC_EFS_CASE_PRESERVE)) {
                     /* Legacy mode, lower case the returned value */
                     __mystrtolower(ret_spec);
                 }
@@ -6878,7 +6897,7 @@ int_pathify_dirspec(const char *dir, char *buf)
         }
 
         /* Under ODS-2 rules, '.' becomes '_', so fix it up */
-        if (!decc_efs_charset) {
+        if (!DECC_EFS_CHARSET) {
              int dir_start = 0;
              char * str = buf;
              if (str[0] == '.') {
@@ -7031,7 +7050,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
   /* New VMS specific format needs translation
    * glob passes filenames with trailing '\n' and expects this preserved.
    */
-  if (decc_posix_compliant_pathnames) {
+  if (DECC_POSIX_COMPLIANT_PATHNAMES) {
     if (! strBEGINs(spec, "\"^UP^")) {
       char * uspec;
       char *tunix;
@@ -7070,7 +7089,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
     cmp_rslt = 0;
 
     /* Look for EFS ^/ */
-    if (decc_efs_charset) {
+    if (DECC_EFS_CHARSET) {
       while (cp1 != NULL) {
 	cp2 = cp1 - 1;
 	if (*cp2 != '^') {
@@ -7084,7 +7103,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
   }
 
   /* Look for "." and ".." */
-  if (decc_filename_unix_report) {
+  if (DECC_FILENAME_UNIX_REPORT) {
     if (spec[0] == '.') {
       if ((spec[1] == '\0') || (spec[1] == '\n')) {
 	cmp_rslt = 1;
@@ -7131,7 +7150,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
   }
 
   /* Special case 1 - sys$posix_root = / */
-  if (!decc_disable_posix_root) {
+  if (!DECC_DISABLE_POSIX_ROOT) {
     if (strncasecmp(spec, "SYS$POSIX_ROOT:", 15) == 0) {
       *cp1 = '/';
       cp1++;
@@ -7289,7 +7308,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
           cp1 += outchars_added;
           break;
       case ';':
-          if (decc_filename_unix_no_version) {
+          if (DECC_FILENAME_UNIX_NO_VERSION) {
               /* Easy, drop the version */
               while (*cp2)
                   cp2++;
@@ -7322,7 +7341,7 @@ int_tounixspec(const char *spec, char *rslt, int * utf8_fl)
           }
           dot_seen = 1;
           /* This is an extension */
-          if (decc_readdir_dropdotnotype) {
+          if (DECC_READDIR_DROPDOTNOTYPE) {
               cp2++;
               if ((!*cp2) || (*cp2 == ';') || (*cp2 == '.')) {
                   /* Drop the dot for the extension */
@@ -7462,7 +7481,7 @@ posix_root_to_vms(char *vmspath, int vmspath_len,
 
 #if __CRTL_VER >= 80200000
   /* If not a posix spec already, convert it */
-  if (decc_posix_compliant_pathnames) {
+  if (DECC_POSIX_COMPLIANT_PATHNAMES) {
     if (! strBEGINs(unixpath,"\"^UP^")) {
       sprintf(vmspath,"\"^UP^%s\"",unixpath);
     }
@@ -7479,7 +7498,7 @@ posix_root_to_vms(char *vmspath, int vmspath_len,
      int i,j;
 
      /* Check to see if this is under the POSIX root */
-     if (decc_disable_posix_root) {
+     if (DECC_DISABLE_POSIX_ROOT) {
 	return RMS$_FNF;
      }
 
@@ -7536,7 +7555,7 @@ posix_root_to_vms(char *vmspath, int vmspath_len,
   rms_bind_fab_nam(myfab, mynam);
   rms_set_esal(mynam, esa, NAM$C_MAXRSS, esal, VMS_MAXRSS - 1);
   rms_set_rsal(mynam, rsa, NAM$C_MAXRSS, rsal, VMS_MAXRSS - 1);
-  if (decc_efs_case_preserve)
+  if (DECC_EFS_CASE_PRESERVE)
     mynam.naml$b_nop |= NAM$M_NO_SHORT_UPCASE;
 #ifdef NAML$M_OPEN_SPECIAL
   mynam.naml$l_input_flags |= NAML$M_OPEN_SPECIAL;
@@ -7766,8 +7785,8 @@ posix_to_vmsspec_hardway(char *vmspath, int vmspath_len, const char *unixpath,
     /* relative paths */
 
     /* If allowing logical names on relative pathnames, then handle here */
-    if ((unixptr[0] != '.') && !decc_disable_to_vms_logname_translation &&
-	!decc_posix_compliant_pathnames) {
+    if ((unixptr[0] != '.') && !DECC_DISABLE_TO_VMS_LOGNAME_TRANSLATION &&
+	!DECC_POSIX_COMPLIANT_PATHNAMES) {
     char * nextslash;
     int seg_len;
     char * trn;
@@ -8065,7 +8084,7 @@ posix_to_vmsspec_hardway(char *vmspath, int vmspath_len, const char *unixpath,
 	/* now we have foo:bar or foo:[000000]bar to decide from */
 	islnm = vmstrnenv(vmspath, esa, 0, fildev, 0);
 
-        if (!islnm && !decc_posix_compliant_pathnames) {
+        if (!islnm && !DECC_POSIX_COMPLIANT_PATHNAMES) {
 	    if (strEQ(vmspath, "bin")) {
 	        /* bin => SYS$SYSTEM: */
 		islnm = vmstrnenv("SYS$SYSTEM:", esa, 0, fildev, 0);
@@ -8433,7 +8452,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
    /* Posix specifications are now a native VMS format */
   /*--------------------------------------------------*/
 #if __CRTL_VER >= 80200000
-  if (decc_posix_compliant_pathnames) {
+  if (DECC_POSIX_COMPLIANT_PATHNAMES) {
     if (strBEGINs(path,"\"^UP^")) {
       posix_to_vmsspec_hardway(rslt, rslt_len, path, dir_flag, utf8_flag);
       return rslt;
@@ -8533,7 +8552,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
 
     while (*(cp2+1) == '/') cp2++;  /* Skip multiple /s */
     if (!*(cp2+1)) {
-      if (decc_disable_posix_root) {
+      if (DECC_DISABLE_POSIX_ROOT) {
 	strcpy(rslt,"sys$disk:[000000]");
       }
       else {
@@ -8566,7 +8585,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
 	*cp1 = 0;
 	islnm = simple_trnlnm(rslt,trndev,VMS_MAXRSS-1);
       }
-      else if (!decc_disable_posix_root) {
+      else if (!DECC_DISABLE_POSIX_ROOT) {
         strcpy(rslt, "sys$posix_root");
 	cp1 = rslt + 14;
 	*cp1 = 0;
@@ -8608,7 +8627,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
         }
       }
       else {
-	if (decc_disable_posix_root) {
+	if (DECC_DISABLE_POSIX_ROOT) {
 	  *(cp1++) = ':';
 	  hasdir = 0;
 	}
@@ -8670,7 +8689,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
         else cp2 += 3;  /* Trailing '/' was there, so skip it, too */
       }
       else {
-        if (decc_efs_charset == 0) {
+        if (DECC_EFS_CHARSET == 0) {
 	  if (cp1 > rslt && *(cp1-1) == '^')
 	    cp1--;         /* remove the escape, if any */
 	  *(cp1++) = '_';  /* fix up syntax - '.' in name not allowed */
@@ -8683,7 +8702,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
     else {
       if (!infront && cp1 > rslt && *(cp1-1) == '-')  *(cp1++) = '.';
       if (*cp2 == '.') {
-        if (decc_efs_charset == 0) {
+        if (DECC_EFS_CHARSET == 0) {
 	  if (cp1 > rslt && *(cp1-1) == '^')
 	    cp1--;         /* remove the escape, if any */
 	  *(cp1++) = '_';
@@ -8710,7 +8729,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
   while (*cp2) {
     switch(*cp2) {
     case '?':
-        if (decc_efs_charset == 0)
+        if (DECC_EFS_CHARSET == 0)
 	  *(cp1++) = '%';
 	else
 	  *(cp1++) = '?';
@@ -8724,7 +8743,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
 	break;
     case '.':
 	if (((cp2 < lastdot) || (cp2[1] == '\0')) &&
-	    decc_readdir_dropdotnotype) {
+	    DECC_READDIR_DROPDOTNOTYPE) {
 	  VMSEFS_DOT_WITH_ESCAPE(cp1, rslt, VMS_MAXRSS);
 	  cp2++;
 
@@ -8810,7 +8829,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
          * or we've been promised there are no version numbers, then
          * escape it.
          */
-	if (decc_filename_unix_no_version) {
+	if (DECC_FILENAME_UNIX_NO_VERSION) {
 	  *(cp1++) = '^';
 	}
 	else {
@@ -8824,7 +8843,7 @@ int_tovmsspec(const char *path, char *rslt, int dir_flag, int * utf8_flag)
 	*(cp1++) = *(cp2++);
     }
   }
-  if ((no_type_seen == 1) && decc_readdir_dropdotnotype) {
+  if ((no_type_seen == 1) && DECC_READDIR_DROPDOTNOTYPE) {
   char *lcp1;
     lcp1 = cp1;
     lcp1--;
@@ -9469,7 +9488,7 @@ mp_expand_wild_cards(pTHX_ char *item, struct list_item **head,
 	 * Be consistent with what the C RTL has already done to the rest of
 	 * the argv items and lowercase all of these names.
 	 */
-	if (!decc_efs_case_preserve) {
+	if (!DECC_EFS_CASE_PRESERVE) {
 	    for (c = string; *c; ++c)
 	    if (isupper(*c))
 		*c = toLOWER_L1(*c);
@@ -9635,36 +9654,6 @@ vms_image_init(int *argcp, char ***argvp)
     Perl_csighandler_init();
 #endif
 
-    /* This was moved from the pre-image init handler because on threaded */
-    /* Perl it was always returning 0 for the default value. */
-    status = simple_trnlnm("SYS$POSIX_ROOT", eqv, LNM$C_NAMLENGTH);
-    if (status > 0) {
-        int s;
-	s = decc$feature_get_index("DECC$DISABLE_POSIX_ROOT");
-	if (s > 0) {
-            int initial;
-	    initial = decc$feature_get_value(s, 4);
-	    if (initial > 0) {
-                /* initial is: 0 if nothing has set the feature */
-                /*            -1 if initialized to default */
-                /*             1 if set by logical name */
-                /*             2 if set by decc$feature_set_value */
-		decc_disable_posix_root = decc$feature_get_value(s, 1);
-
-                /* If the value is not valid, force the feature off */
-		if (decc_disable_posix_root < 0) {
-		    decc$feature_set_value(s, 1, 1);
-		    decc_disable_posix_root = 1;
-		}
-	    }
-	    else {
-		/* Nothing has asked for it explicitly, so use our own default. */
-		decc_disable_posix_root = 1;
-		decc$feature_set_value(s, 1, 1);
-	    }
-	}
-    }
-
   _ckvmssts_noperl(sys$getjpiw(0,NULL,NULL,jpilist,iosb,NULL,NULL));
   _ckvmssts_noperl(iosb[0]);
   for (i = 0; i < sizeof iprv / sizeof(unsigned long int); i++) {
@@ -9715,7 +9704,7 @@ vms_image_init(int *argcp, char ***argvp)
    * logical, some versions of the CRTL will add a phanthom /000000/
    * directory.  This needs to be removed.
    */
-  if (decc_filename_unix_report) {
+  if (DECC_FILENAME_UNIX_REPORT) {
     char * zeros;
     int ulen;
     ulen = strlen(argvp[0][0]);
@@ -9733,7 +9722,7 @@ vms_image_init(int *argcp, char ***argvp)
      * it will be converted to VMS mode incorrectly.
      */
     ulen--;
-    if ((argvp[0][0][ulen] == '.') && (decc_readdir_dropdotnotype))
+    if ((argvp[0][0][ulen] == '.') && (DECC_READDIR_DROPDOTNOTYPE))
       argvp[0][0][ulen] = '\0';
   }
 
@@ -9915,7 +9904,7 @@ Perl_trim_unixpath(pTHX_ char *fspec, const char *wildspec, int opts)
 	  PerlMem_free(unixwild);
 	  return 0;
       }
-      if (!decc_efs_case_preserve) {
+      if (!DECC_EFS_CASE_PRESERVE) {
  	for (cp1 = tpl, cp2 = base; *cp1 && *cp2; cp1++,cp2++)
 	  if (toLOWER_L1(*cp1) != toLOWER_L1(*cp2)) break;
       }
@@ -9938,7 +9927,7 @@ Perl_trim_unixpath(pTHX_ char *fspec, const char *wildspec, int opts)
     if (lcres == NULL) _ckvmssts_noperl(SS$_INSFMEM);
     for (cp1=tplate,cp2=lcres; *cp1 && cp2 <= lcres + (VMS_MAXRSS - 1);
          cp1++,cp2++) {
-	    if (!decc_efs_case_preserve) {
+	    if (!DECC_EFS_CASE_PRESERVE) {
 		*cp2 = toLOWER_L1(*cp1);  /* Make lc copy for match */
 	    }
 	    else {
@@ -9972,7 +9961,7 @@ Perl_trim_unixpath(pTHX_ char *fspec, const char *wildspec, int opts)
            cp1++, cp2++) {
          if (*cp1 == '?') *cp2 = '%'; /* Substitute VMS' wildcard for Unix' */
          else {
-	    if (!decc_efs_case_preserve) {
+	    if (!DECC_EFS_CASE_PRESERVE) {
 	      *cp2 = toLOWER_L1(*cp1);  /* else lowercase for match */
 	    }
 	    else {
@@ -10024,7 +10013,7 @@ Perl_trim_unixpath(pTHX_ char *fspec, const char *wildspec, int opts)
 	    PerlMem_free(tpl);
 	    return 0;
 	}
-	if (!decc_efs_case_preserve) {
+	if (!DECC_EFS_CASE_PRESERVE) {
 	  for (cp1 = def, cp2 = base; *cp1 && *cp2; cp1++,cp2++)
 	    if (toLOWER_L1(*cp1) != toLOWER_L1(*cp2)) break;
 	}
@@ -10122,7 +10111,7 @@ Perl_opendir(pTHX_ const char *name)
      * must be escaped in a VMS-format name to their unescaped form, which is
      * presumably allowed in a Unix-format name.
      */
-    dd->flags = decc_filename_unix_report ? PERL_VMSDIR_M_UNIXSPECS : 0;
+    dd->flags = DECC_FILENAME_UNIX_REPORT ? PERL_VMSDIR_M_UNIXSPECS : 0;
     dd->pat.dsc$a_pointer = dd->pattern;
     dd->pat.dsc$w_length = strlen(dd->pattern);
     dd->pat.dsc$b_dtype = DSC$K_DTYPE_T;
@@ -10287,7 +10276,7 @@ Perl_readdir(pTHX_ DIR *dd)
     p = buff + res.dsc$w_length;
     while (--p >= buff) if (!isSPACE_L1(*p)) break;  
     *p = '\0';
-    if (!decc_efs_case_preserve) {
+    if (!DECC_EFS_CASE_PRESERVE) {
       for (p = buff; *p; p++) *p = toLOWER_L1(*p);
     }
 
@@ -10311,7 +10300,7 @@ Perl_readdir(pTHX_ DIR *dd)
 
         /* In Unix report mode, remove the ".dir;1" from the name */
         /* if it is a real directory. */
-        if (decc_filename_unix_report && decc_efs_charset) {
+        if (DECC_FILENAME_UNIX_REPORT && DECC_EFS_CHARSET) {
             if (is_dir_ext(e_spec, e_len, vs_spec, vs_len)) {
                 Stat_t statbuf;
                 int ret_sts;
@@ -10325,7 +10314,7 @@ Perl_readdir(pTHX_ DIR *dd)
         }
 
         /* Drop NULL extensions on UNIX file specification */
-	if ((e_len == 1) && decc_readdir_dropdotnotype) {
+	if ((e_len == 1) && DECC_READDIR_DROPDOTNOTYPE) {
 	    e_len = 0;
 	    e_spec[0] = '\0';
         }
@@ -10670,7 +10659,7 @@ setup_cmddsc(pTHX_ const char *incmd, int check_img, int *suggest_quote,
       /* A trailing '.' is appended under ODS-5 rules.            */
       /* Here we do not want that trailing "." as it prevents     */
       /* Looking for a implied ".exe" type. */
-      if (decc_efs_charset) {
+      if (DECC_EFS_CHARSET) {
           int i;
           i = strlen(vmsspec);
           if (vmsspec[i-1] == '.') {
@@ -11268,7 +11257,7 @@ Perl_my_fgetname(FILE *fp, char * buf) {
     retname = fgetname(fp, buf, 1);
 
     /* If we are in VMS mode, then we are done */
-    if (!decc_filename_unix_report || (retname == NULL)) {
+    if (!DECC_FILENAME_UNIX_REPORT || (retname == NULL)) {
        return retname;
     }
 
@@ -11416,7 +11405,7 @@ fillpasswd (pTHX_ const char *name, struct passwd *pwd)
     }
     else
         my_strlcpy(pwd->pw_unixdir, pwd->pw_dir, sizeof(pwd->pw_unixdir));
-    if (!decc_efs_case_preserve)
+    if (!DECC_EFS_CASE_PRESERVE)
         __mystrtolower(pwd->pw_unixdir);
     return 1;
 }
@@ -12126,7 +12115,7 @@ Perl_flex_stat_int(pTHX_ const char *fspec, Stat_t *statbufp, int lstat_flag)
   /*
    * If we are in POSIX filespec mode, accept the filename as is.
    */
-  if (decc_posix_compliant_pathnames == 0) {
+  if (!DECC_POSIX_COMPLIANT_PATHNAMES) {
 #endif
 
     /* Try for a simple stat first.  If fspec contains a filename without
@@ -12189,15 +12178,15 @@ Perl_flex_stat_int(pTHX_ const char *fspec, Stat_t *statbufp, int lstat_flag)
          * format unless * DECC$EFS_CHARSET is in effect, so temporarily
          * enable it if it isn't already.
          */
-        if (!decc_efs_charset && (decc_efs_charset_index > 0))
-            decc$feature_set_value(decc_efs_charset_index, 1, 1); 
+        if (!DECC_EFS_CHARSET && (efs_charset_index > 0))
+            decc$feature_set_value(efs_charset_index, 1, 1);
         if (lstat_flag == 0)
 	    retval = stat(fspec, &statbufp->crtl_stat);
         else
 	    retval = lstat(fspec, &statbufp->crtl_stat);
         save_spec = fspec;
-        if (!decc_efs_charset && (decc_efs_charset_index > 0)) {
-            decc$feature_set_value(decc_efs_charset_index, 1, 0); 
+        if (!DECC_EFS_CHARSET && (efs_charset_index > 0)) {
+            decc$feature_set_value(efs_charset_index, 1, 0);
             efs_hack = 1;
         }
     }
@@ -12213,8 +12202,8 @@ Perl_flex_stat_int(pTHX_ const char *fspec, Stat_t *statbufp, int lstat_flag)
 #endif
 
   /* As you were... */
-  if (!decc_efs_charset)
-    decc$feature_set_value(decc$feature_get_index("DECC$EFS_CHARSET"),1,0); 
+  if (!DECC_EFS_CHARSET)
+    decc$feature_set_value(efs_charset_index,1,0);
 
     if (!retval) {
       char *cptr;
@@ -12226,8 +12215,8 @@ Perl_flex_stat_int(pTHX_ const char *fspec, Stat_t *statbufp, int lstat_flag)
 
       /* If we used the efs_hack above, we must also use it here for */
       /* perl_cando to work */
-      if (efs_hack && (decc_efs_charset_index > 0)) {
-          decc$feature_set_value(decc_efs_charset_index, 1, 1);
+      if (efs_hack && (efs_charset_index > 0)) {
+          decc$feature_set_value(efs_charset_index, 1, 1);
       }
 
       /* If we've got a directory, save a fileified, expanded version of it
@@ -12250,8 +12239,8 @@ Perl_flex_stat_int(pTHX_ const char *fspec, Stat_t *statbufp, int lstat_flag)
                            0,
                            0);
 
-      if (efs_hack && (decc_efs_charset_index > 0)) {
-          decc$feature_set_value(decc_efs_charset, 1, 0);
+      if (efs_hack && (efs_charset_index > 0)) {
+          decc$feature_set_value(efs_charset_index, 1, 0);
       }
 
       /* Fix me: If this is NULL then stat found a file, and we could */
@@ -12380,7 +12369,7 @@ Perl_rmscopy(pTHX_ const char *spec_in, const char *spec_out, int preserve_dates
     rms_nam_esll(nam) = 0;
     rms_nam_rsll(nam) = 0;
 #ifdef NAM$M_NO_SHORT_UPCASE
-    if (decc_efs_case_preserve)
+    if (DECC_EFS_CASE_PRESERVE)
 	rms_set_nam_nop(nam, NAM$M_NO_SHORT_UPCASE);
 #endif
 
@@ -13000,7 +12989,7 @@ Perl_vms_start_glob(pTHX_ SV *tmpglob, IO *io)
         return NULL;
     }
 
-    vms_old_glob = !decc_filename_unix_report;
+    vms_old_glob = !DECC_FILENAME_UNIX_REPORT;
 
 #ifdef VMS_LONGNAME_SUPPORT
     lff_flags = LIB$M_FIL_LONG_NAMES;
@@ -13048,7 +13037,7 @@ Perl_vms_start_glob(pTHX_ SV *tmpglob, IO *io)
     }
 
     /* In UNIX report mode, assume UNIX unless VMS directory delimiters seen */
-    if ((hasdir == 0) && decc_filename_unix_report) {
+    if ((hasdir == 0) && DECC_FILENAME_UNIX_REPORT) {
         isunix = 1;
     }
 
@@ -13100,7 +13089,7 @@ Perl_vms_start_glob(pTHX_ SV *tmpglob, IO *io)
 	for (cp=wilddsc.dsc$a_pointer; ok && cp && *cp; cp++) {
 	    if (*cp == '?') {
                 wildquery = 1;
-                if (!decc_efs_charset)
+                if (!DECC_EFS_CHARSET)
                     *cp = '%';
             } else if (*cp == '%') {
                 wildquery = 1;
@@ -13162,7 +13151,7 @@ Perl_vms_start_glob(pTHX_ SV *tmpglob, IO *io)
 
                 /* In Unix report mode, remove the ".dir;1" from the name */
                 /* if it is a real directory */
-                if (decc_filename_unix_report && decc_efs_charset) {
+                if (DECC_FILENAME_UNIX_REPORT && DECC_EFS_CHARSET) {
                     if (is_dir_ext(e_spec, e_len, vs_spec, vs_len)) {
                         Stat_t statbuf;
                         int ret_sts;
@@ -13177,13 +13166,13 @@ Perl_vms_start_glob(pTHX_ SV *tmpglob, IO *io)
                 }
 
 		/* No version & a null extension on UNIX handling */
-		if ((e_len == 1) && decc_readdir_dropdotnotype) {
+		if ((e_len == 1) && DECC_READDIR_DROPDOTNOTYPE) {
 		    e_len = 0;
 		    *e_spec = '\0';
 		}
 	    }
 
-	    if (!decc_efs_case_preserve) {
+	    if (!DECC_EFS_CASE_PRESERVE) {
 	        for (cp = rstr; *cp; cp++) *cp = toLOWER_L1(*cp);
 	    }
 
@@ -13391,7 +13380,7 @@ init_os_extras(void)
 {
   dTHX;
   char* file = __FILE__;
-  if (decc_disable_to_vms_logname_translation) {
+  if (DECC_DISABLE_TO_VMS_LOGNAME_TRANSLATION) {
     no_translate_barewords = TRUE;
   } else {
     no_translate_barewords = FALSE;
@@ -13521,16 +13510,16 @@ int vms_fid_to_name(char * outname, int outlen,
          * format unless * DECC$EFS_CHARSET is in effect, so temporarily
          * enable it if it isn't already.
          */
-        if (!decc_efs_charset && (decc_efs_charset_index > 0))
-            decc$feature_set_value(decc_efs_charset_index, 1, 1); 
+        if (!DECC_EFS_CHARSET && (efs_charset_index > 0))
+            decc$feature_set_value(efs_charset_index, 1, 1);
         ret_spec = int_tovmspath(name, temp_fspec, NULL);
         if (lstat_flag == 0) {
             sts = decc$stat(name, &statbuf);
         } else {
             sts = decc$lstat(name, &statbuf);
         }
-        if (!decc_efs_charset && (decc_efs_charset_index > 0))
-            decc$feature_set_value(decc_efs_charset_index, 1, 0); 
+        if (!DECC_EFS_CHARSET && (efs_charset_index > 0))
+            decc$feature_set_value(efs_charset_index, 1, 0);
     }
 
 
@@ -13579,7 +13568,7 @@ mp_do_vms_realpath(pTHX_ const char *filespec, char *outbuf,
     char * rslt = NULL;
 
 #ifdef HAS_SYMLINK
-    if (decc_posix_compliant_pathnames > 0 ) {
+    if (DECC_POSIX_COMPLIANT_PATHNAMES) {
 	/* realpath currently only works if posix compliant pathnames are
 	 * enabled.  It may start working when they are not, but in that
 	 * case we still want the fallback behavior for backwards compatibility
@@ -13636,7 +13625,7 @@ mp_do_vms_realpath(pTHX_ const char *filespec, char *outbuf,
 	            }
 
 	            /* Drop NULL extensions on UNIX file specification */
-		    if ((e_len == 1) && decc_readdir_dropdotnotype) {
+		    if ((e_len == 1) && DECC_READDIR_DROPDOTNOTYPE) {
 			e_len = 0;
 			e_spec[0] = '\0';
 		    }
@@ -13647,7 +13636,7 @@ mp_do_vms_realpath(pTHX_ const char *filespec, char *outbuf,
                     /* Downcase if input had any lower case letters and 
 	             * case preservation is not in effect. 
 	             */
-	            if (!decc_efs_case_preserve) {
+	            if (!DECC_EFS_CASE_PRESERVE) {
 	                for (cp = filespec; *cp; cp++)
 	                    if (islower(*cp)) { haslower = 1; break; }
 
@@ -13658,14 +13647,14 @@ mp_do_vms_realpath(pTHX_ const char *filespec, char *outbuf,
 
 	    /* Now for some hacks to deal with backwards and forward */
 	    /* compatibility */
-	    if (!decc_efs_charset) {
+	    if (!DECC_EFS_CHARSET) {
 
 		/* 1. ODS-2 mode wants to do a syntax only translation */
 		rslt = int_rmsexpand(filespec, outbuf,
 				    NULL, 0, NULL, utf8_fl);
 
 	    } else {
-		if (decc_filename_unix_report) {
+		if (DECC_FILENAME_UNIX_REPORT) {
 		    char * dir_name;
 		    char * vms_dir_name;
 		    char * file_name;
@@ -13798,7 +13787,7 @@ mp_do_vms_realname(pTHX_ const char *filespec, char *outbuf,
 	    /* Downcase if input had any lower case letters and 
 	     * case preservation is not in effect. 
 	     */
-	    if (!decc_efs_case_preserve) {
+	    if (!DECC_EFS_CASE_PRESERVE) {
 	        for (cp = filespec; *cp; cp++)
 	            if (islower(*cp)) { haslower = 1; break; }
 
@@ -13896,9 +13885,9 @@ extern "C" {
 extern void
 vmsperl_set_features(void)
 {
-    int status;
+    int status, initial;
     int s;
-    char val_str[10];
+    char val_str[LNM$C_NAMLENGTH+1];
 #if defined(JPI$_CASE_LOOKUP_PERM)
     const unsigned long int jpicode1 = JPI$_CASE_LOOKUP_PERM;
     const unsigned long int jpicode2 = JPI$_CASE_LOOKUP_IMAGE;
@@ -13995,6 +13984,20 @@ vmsperl_set_features(void)
     set_feature_default("DECC$ARGV_PARSE_STYLE", 1);     /* Requires extended parse. */
     set_feature_default("DECC$EFS_CHARSET", 1);
 
+   /* If POSIX root doesn't exist or nothing has set it explicitly, we disable it,
+    * which confusingly means enabling the feature.  For some reason only the default
+    * -- not current -- value can be set, so we cannot use the confusingly-named
+    * set_feature_default function, which sets the current value.
+    */
+    s = decc$feature_get_index("DECC$DISABLE_POSIX_ROOT");
+    disable_posix_root_index = s;
+
+    status = simple_trnlnm("SYS$POSIX_ROOT", val_str, LNM$C_NAMLENGTH);
+    initial = decc$feature_get_value(disable_posix_root_index, __FEATURE_MODE_INIT_STATE);
+    if (!status || !initial) {
+        decc$feature_set_value(disable_posix_root_index, 0, 1);
+    }
+
     /* hacks to see if known bugs are still present for testing */
 
     /* PCP mode requires creating /dev/null special device file */
@@ -14009,73 +14012,29 @@ vmsperl_set_features(void)
     }
 
     s = decc$feature_get_index("DECC$DISABLE_TO_VMS_LOGNAME_TRANSLATION");
-    if (s >= 0) {
-	decc_disable_to_vms_logname_translation = decc$feature_get_value(s, 1);
-	if (decc_disable_to_vms_logname_translation < 0)
-	    decc_disable_to_vms_logname_translation = 0;
-    }
+    disable_to_vms_logname_translation_index = s;
 
     s = decc$feature_get_index("DECC$EFS_CASE_PRESERVE");
-    if (s >= 0) {
-	decc_efs_case_preserve = decc$feature_get_value(s, 1);
-	if (decc_efs_case_preserve < 0)
-	    decc_efs_case_preserve = 0;
-    }
+    efs_case_preserve_index = s;
 
     s = decc$feature_get_index("DECC$EFS_CHARSET");
-    decc_efs_charset_index = s;
-    if (s >= 0) {
-	decc_efs_charset = decc$feature_get_value(s, 1);
-	if (decc_efs_charset < 0)
-	    decc_efs_charset = 0;
-    }
+    efs_charset_index = s;
 
     s = decc$feature_get_index("DECC$FILENAME_UNIX_REPORT");
-    if (s >= 0) {
-	decc_filename_unix_report = decc$feature_get_value(s, 1);
-	if (decc_filename_unix_report > 0) {
-	    decc_filename_unix_report = 1;
-	    vms_posix_exit = 1;
-	}
-	else
-	    decc_filename_unix_report = 0;
-    }
+    filename_unix_report_index = s;
 
     s = decc$feature_get_index("DECC$FILENAME_UNIX_ONLY");
-    if (s >= 0) {
-	decc_filename_unix_only = decc$feature_get_value(s, 1);
-	if (decc_filename_unix_only > 0) {
-	    decc_filename_unix_only = 1;
-	}
-	else {
-	    decc_filename_unix_only = 0;
-	}
-    }
+    filename_unix_only_index = s;
 
     s = decc$feature_get_index("DECC$FILENAME_UNIX_NO_VERSION");
-    if (s >= 0) {
-	decc_filename_unix_no_version = decc$feature_get_value(s, 1);
-	if (decc_filename_unix_no_version < 0)
-	    decc_filename_unix_no_version = 0;
-    }
+    filename_unix_no_version_index = s;
 
     s = decc$feature_get_index("DECC$READDIR_DROPDOTNOTYPE");
-    if (s >= 0) {
-	decc_readdir_dropdotnotype = decc$feature_get_value(s, 1);
-	if (decc_readdir_dropdotnotype < 0)
-	    decc_readdir_dropdotnotype = 0;
-    }
+    readdir_dropdotnotype_index = s;
 
 #if __CRTL_VER >= 80200000
     s = decc$feature_get_index("DECC$POSIX_COMPLIANT_PATHNAMES");
-    if (s >= 0) {
-	decc_posix_compliant_pathnames = decc$feature_get_value(s, 1);
-	if (decc_posix_compliant_pathnames < 0)
-	    decc_posix_compliant_pathnames = 0;
-	if (decc_posix_compliant_pathnames > 4)
-	    decc_posix_compliant_pathnames = 0;
-    }
-
+    posix_compliant_pathnames_index = s;
 #endif
 
 #if defined(JPI$_CASE_LOOKUP_PERM) && defined(PPROP$K_CASE_BLIND)