+SV *
+PerlIO_sv_dup(pTHX_ SV *arg, CLONE_PARAMS *param)
+{
+ if (!arg)
+ return Nullsv;
+#ifdef sv_dup
+ if (param) {
+ return sv_dup(arg, param);
+ }
+ else {
+ return newSVsv(arg);
+ }
+#else
+ return newSVsv(arg);
+#endif
+}
+
+PerlIO *
+PerlIOBase_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
+{
+ PerlIO *nexto = PerlIONext(o);
+ if (PerlIOValid(nexto)) {
+ PerlIO_funcs *tab = PerlIOBase(nexto)->tab;
+ f = (*tab->Dup)(aTHX_ f, nexto, param, flags);
+ }
+ if (f) {
+ PerlIO_funcs *self = PerlIOBase(o)->tab;
+ SV *arg = Nullsv;
+ char buf[8];
+ PerlIO_debug("PerlIOBase_dup %s f=%p o=%p param=%p\n",
+ self->name, (void*)f, (void*)o, (void*)param);
+ if (self->Getarg) {
+ arg = (*self->Getarg)(aTHX_ o,param,flags);
+ }
+ f = PerlIO_push(aTHX_ f, self, PerlIO_modestr(o,buf), arg);
+ if (arg) {
+ SvREFCNT_dec(arg);
+ }
+ }
+ return f;
+}
+
+#define PERLIO_MAX_REFCOUNTABLE_FD 2048
+#ifdef USE_THREADS
+perl_mutex PerlIO_mutex;
+#endif
+int PerlIO_fd_refcnt[PERLIO_MAX_REFCOUNTABLE_FD];
+
+void
+PerlIO_init(pTHX)
+{
+ /* Place holder for stdstreams call ??? */
+#ifdef USE_THREADS
+ MUTEX_INIT(&PerlIO_mutex);
+#endif
+}
+
+void
+PerlIOUnix_refcnt_inc(int fd)
+{
+ if (fd >= 0 && fd < PERLIO_MAX_REFCOUNTABLE_FD) {
+#ifdef USE_THREADS
+ MUTEX_LOCK(&PerlIO_mutex);
+#endif
+ PerlIO_fd_refcnt[fd]++;
+ PerlIO_debug("fd %d refcnt=%d\n",fd,PerlIO_fd_refcnt[fd]);
+#ifdef USE_THREADS
+ MUTEX_UNLOCK(&PerlIO_mutex);
+#endif
+ }
+}
+
+int
+PerlIOUnix_refcnt_dec(int fd)
+{
+ int cnt = 0;
+ if (fd >= 0 && fd < PERLIO_MAX_REFCOUNTABLE_FD) {
+#ifdef USE_THREADS
+ MUTEX_LOCK(&PerlIO_mutex);
+#endif
+ cnt = --PerlIO_fd_refcnt[fd];
+ PerlIO_debug("fd %d refcnt=%d\n",fd,cnt);
+#ifdef USE_THREADS
+ MUTEX_UNLOCK(&PerlIO_mutex);
+#endif
+ }
+ return cnt;
+}
+
+void
+PerlIO_cleanup(pTHX)
+{
+ int i;
+#ifdef USE_ITHREADS
+ PerlIO_debug("Cleanup layers for %p\n",aTHX);
+#else
+ PerlIO_debug("Cleanup layers\n");
+#endif
+ /* Raise STDIN..STDERR refcount so we don't close them */
+ for (i=0; i < 3; i++)
+ PerlIOUnix_refcnt_inc(i);
+ PerlIO_cleantable(aTHX_ &PL_perlio);
+ /* Restore STDIN..STDERR refcount */
+ for (i=0; i < 3; i++)
+ PerlIOUnix_refcnt_dec(i);
+
+ if (PL_known_layers) {
+ PerlIO_list_free(aTHX_ PL_known_layers);
+ PL_known_layers = NULL;
+ }
+ if(PL_def_layerlist) {
+ PerlIO_list_free(aTHX_ PL_def_layerlist);
+ PL_def_layerlist = NULL;
+ }
+}
+
+
+