another threads reliability fix: serialize writes to thr->threadsv

avoid most uses of PL_na (which is much more inefficient than a
simple local); update docs to suit; PL_na now being thr->Tna may
be a minor compatibility issue for extensions--will require dTHR
outside of XSUBs (those get automatic dTHR)

p4raw-id: //depot/perl@2387

1 files changed, 17 insertions, 9 deletions

diff --git a/pod/perlembed.pod b/pod/perlembed.pod
index c09d6e33cb..1314350f9e 100644
--- a/pod/perlembed.pod
+++ b/pod/perlembed.pod
@@ -285,6 +285,7 @@ the first, a C<float> from the second, and a C<char *> from the third.
    
    main (int argc, char **argv, char **env)
    {
+       STRLEN n_a;
        char *embedding[] = { "", "-e", "0" };
    
        my_perl = perl_alloc();
@@ -303,7 +304,7 @@ the first, a C<float> from the second, and a C<char *> from the third.
    
        /** Treat $a as a string **/
        perl_eval_pv("$a = 'rekcaH lreP rehtonA tsuJ'; $a = reverse($a);", TRUE);
-       printf("a = %s\n", SvPV(perl_get_sv("a", FALSE), PL_na));
+       printf("a = %s\n", SvPV(perl_get_sv("a", FALSE), n_a));
    
        perl_destruct(my_perl);
        perl_free(my_perl);
@@ -325,8 +326,9 @@ possible and in most cases a better strategy to fetch the return value
 from I<perl_eval_pv()> instead.  Example:
 
    ...
+   STRLEN n_a;
    SV *val = perl_eval_pv("reverse 'rekcaH lreP rehtonA tsuJ'", TRUE);
-   printf("%s\n", SvPV(val,PL_na));
+   printf("%s\n", SvPV(val,n_a));
    ...
 
 This way, we avoid namespace pollution by not creating global
@@ -371,6 +373,7 @@ been wrapped here):
  {
      dSP;
      SV* retval;
+     STRLEN n_a;
  
      PUSHMARK(SP);
      perl_eval_sv(sv, G_SCALAR);
@@ -380,7 +383,7 @@ been wrapped here):
      PUTBACK;
  
      if (croak_on_error && SvTRUE(ERRSV))
- 	croak(SvPVx(ERRSV, PL_na));
+ 	croak(SvPVx(ERRSV, n_a));
  
      return retval;
  }
@@ -395,9 +398,10 @@ been wrapped here):
  I32 match(SV *string, char *pattern)
  {
      SV *command = NEWSV(1099, 0), *retval;
+     STRLEN n_a;
  
      sv_setpvf(command, "my $string = '%s'; $string =~ %s",
- 	      SvPV(string,PL_na), pattern);
+ 	      SvPV(string,n_a), pattern);
  
      retval = my_perl_eval_sv(command, TRUE);
      SvREFCNT_dec(command);
@@ -416,9 +420,10 @@ been wrapped here):
  I32 substitute(SV **string, char *pattern)
  {
      SV *command = NEWSV(1099, 0), *retval;
+     STRLEN n_a;
  
      sv_setpvf(command, "$string = '%s'; ($string =~ %s)",
- 	      SvPV(*string,PL_na), pattern);
+ 	      SvPV(*string,n_a), pattern);
  
      retval = my_perl_eval_sv(command, TRUE);
      SvREFCNT_dec(command);
@@ -439,9 +444,10 @@ been wrapped here):
  {
      SV *command = NEWSV(1099, 0);
      I32 num_matches;
+     STRLEN n_a;
  
      sv_setpvf(command, "my $string = '%s'; @array = ($string =~ %s)",
- 	      SvPV(string,PL_na), pattern);
+ 	      SvPV(string,n_a), pattern);
  
      my_perl_eval_sv(command, TRUE);
      SvREFCNT_dec(command);
@@ -459,6 +465,7 @@ been wrapped here):
      AV *match_list;
      I32 num_matches, i;
      SV *text = NEWSV(1099,0);
+     STRLEN n_a;
  
      perl_construct(my_perl);
      perl_parse(my_perl, NULL, 3, embedding, NULL);
@@ -480,7 +487,7 @@ been wrapped here):
      printf("matches: m/(wi..)/g found %d matches...\n", num_matches);
  
      for (i = 0; i < num_matches; i++)
- 	printf("match: %s\n", SvPV(*av_fetch(match_list, i, FALSE),PL_na));
+ 	printf("match: %s\n", SvPV(*av_fetch(match_list, i, FALSE),n_a));
      printf("\n");
  
      /** Remove all vowels from text **/
@@ -488,7 +495,7 @@ been wrapped here):
      if (num_matches) {
  	printf("substitute: s/[aeiou]//gi...%d substitutions made.\n",
  	       num_matches);
- 	printf("Now text is: %s\n\n", SvPV(text,PL_na));
+ 	printf("Now text is: %s\n\n", SvPV(text,n_a));
      }
  
      /** Attempt a substitution **/
@@ -726,6 +733,7 @@ with L<perlfunc/my> whenever possible.
      char *args[] = { "", DO_CLEAN, NULL };
      char filename [1024];
      int exitstatus = 0;
+     STRLEN n_a;
 
      if((perl = perl_alloc()) == NULL) {
         fprintf(stderr, "no memory!");
@@ -747,7 +755,7 @@ with L<perlfunc/my> whenever possible.
 
             /* check $@ */
             if(SvTRUE(ERRSV))
-                fprintf(stderr, "eval error: %s\n", SvPV(ERRSV,PL_na));
+                fprintf(stderr, "eval error: %s\n", SvPV(ERRSV,n_a));
         }
      }