Revert "make PerlIO handle FD_CLOEXEC"

This reverts commit 2cdf406af42834c46ef407517daab0734f7066fc.

The reason for the revert is that with this commit, perl fails to
compile on darwin (or at least, one some versions of it):

    ./miniperl -Ilib make_ext.pl lib/auto/DB_File/DB_File.bundle  MAKE="/Applications/Xcode.app/Contents/Developer/usr/bin/make" LIBPERL_A=libperl.a LINKTYPE=dynamic
    Parsing config.in...
    Looks Good.
    dyld: lazy symbol binding failed: Symbol not found: _mkostemp
      Referenced from: /private/tmp/perl/cpan/DB_File/../../miniperl
      Expected in: flat namespace

    dyld: Symbol not found: _mkostemp
      Referenced from: /private/tmp/perl/cpan/DB_File/../../miniperl
      Expected in: flat namespace

    Unsuccessful Makefile.PL(cpan/DB_File): code=5 at make_ext.pl line 518.
    make: *** [lib/auto/DB_File/DB_File.bundle] Error 2

10 files changed, 71 insertions, 85 deletions

diff --git a/doio.c b/doio.c
index 4b8923f77c..d18e335a04 100644
--- a/doio.c
+++ b/doio.c
@@ -79,30 +79,12 @@ Perl_setfd_inhexec(int fd)
 }
 
 void
-Perl_setfd_cloexec_for_nonsysfd(pTHX_ int fd)
-{
-    assert(fd >= 0);
-    if(fd > PL_maxsysfd)
-	setfd_cloexec(fd);
-}
-
-void
 Perl_setfd_inhexec_for_sysfd(pTHX_ int fd)
 {
     assert(fd >= 0);
     if(fd <= PL_maxsysfd)
 	setfd_inhexec(fd);
 }
-void
-Perl_setfd_cloexec_or_inhexec_by_sysfdness(pTHX_ int fd)
-{
-    assert(fd >= 0);
-    if(fd <= PL_maxsysfd)
-	setfd_inhexec(fd);
-    else
-	setfd_cloexec(fd);
-}
-
 
 #define DO_GENOPEN_THEN_CLOEXEC(GENOPEN_NORMAL, GENSETFD_CLOEXEC) \
 	do { \
@@ -718,7 +700,7 @@ Perl_do_open6(pTHX_ GV *gv, const char *oname, STRLEN len,
 		    }
 		    else {
 			if (dodup)
-                            wanted_fd = PerlLIO_dup_cloexec(wanted_fd);
+                            wanted_fd = PerlLIO_dup(wanted_fd);
 			else
 			    was_fdopen = TRUE;
                         if (!(fp = PerlIO_openn(aTHX_ type,mode,wanted_fd,0,0,NULL,num_svs,svp))) {
@@ -1009,15 +991,33 @@ S_openn_cleanup(pTHX_ GV *gv, IO *io, PerlIO *fp, char *mode, const char *oname,
 	    if (was_fdopen) {
                 /* need to close fp without closing underlying fd */
                 int ofd = PerlIO_fileno(fp);
-                int dupfd = ofd >= 0 ? PerlLIO_dup_cloexec(ofd) : -1;
+                int dupfd = ofd >= 0 ? PerlLIO_dup(ofd) : -1;
+#if defined(HAS_FCNTL) && defined(F_SETFD)
+		/* Assume if we have F_SETFD we have F_GETFD. */
+                /* Get a copy of all the fd flags. */
+                int fd_flags = ofd >= 0 ? fcntl(ofd, F_GETFD) : -1;
+                if (fd_flags < 0) {
+                    if (dupfd >= 0)
+                        PerlLIO_close(dupfd);
+                    goto say_false;
+                }
+#endif
                 if (ofd < 0 || dupfd < 0) {
                     if (dupfd >= 0)
                         PerlLIO_close(dupfd);
                     goto say_false;
                 }
                 PerlIO_close(fp);
-                PerlLIO_dup2_cloexec(dupfd, ofd);
-                setfd_inhexec_for_sysfd(ofd);
+                PerlLIO_dup2(dupfd, ofd);
+#if defined(HAS_FCNTL) && defined(F_SETFD)
+		/* The dup trick has lost close-on-exec on ofd,
+                 * and possibly any other flags, so restore them. */
+		if (fcntl(ofd,F_SETFD, fd_flags) < 0) {
+                    if (dupfd >= 0)
+                        PerlLIO_close(dupfd);
+                    goto say_false;
+                }
+#endif
                 PerlLIO_close(dupfd);
 	    }
             else
@@ -1027,6 +1027,10 @@ S_openn_cleanup(pTHX_ GV *gv, IO *io, PerlIO *fp, char *mode, const char *oname,
 	PerlIO_clearerr(fp);
 	fd = PerlIO_fileno(fp);
     }
+    if (fd >= 0) {
+	setfd_cloexec(fd);
+	setfd_inhexec_for_sysfd(fd);
+    }
     IoIFP(io) = fp;
 
     IoFLAGS(io) &= ~IOf_NOLINE;
@@ -1096,7 +1100,7 @@ S_openindirtemp(pTHX_ GV *gv, SV *orig_name, SV *temp_out_name) {
 
     {
       int old_umask = umask(0177);
-      fd = Perl_my_mkstemp_cloexec(SvPVX(temp_out_name));
+      fd = Perl_my_mkstemp(SvPVX(temp_out_name));
       umask(old_umask);
     }
 
diff --git a/embed.fnc b/embed.fnc
index cd654dd1e7..adb4178a20 100644
--- a/embed.fnc
+++ b/embed.fnc
@@ -466,11 +466,9 @@ Ap	|bool	|do_open9	|NN GV *gv|NN const char *name|I32 len|int as_raw \
 				|NN SV *svs|I32 num
 pn	|void	|setfd_cloexec|int fd
 pn	|void	|setfd_inhexec|int fd
-p	|void	|setfd_cloexec_for_nonsysfd|int fd
 p	|void	|setfd_inhexec_for_sysfd|int fd
-p	|void	|setfd_cloexec_or_inhexec_by_sysfdness|int fd
 pR	|int	|PerlLIO_dup_cloexec|int oldfd
-p	|int	|PerlLIO_dup2_cloexec|int oldfd|int newfd
+pR	|int	|PerlLIO_dup2_cloexec|int oldfd|int newfd
 pR	|int	|PerlLIO_open_cloexec|NN const char *file|int flag
 pR	|int	|PerlLIO_open3_cloexec|NN const char *file|int flag|int perm
 pnoR	|int	|my_mkstemp_cloexec|NN char *templte
diff --git a/embed.h b/embed.h
index c968191616..08d1cc5f4a 100644
--- a/embed.h
+++ b/embed.h
@@ -1391,8 +1391,6 @@
 #define set_numeric_standard()	Perl_set_numeric_standard(aTHX)
 #define set_numeric_underlying()	Perl_set_numeric_underlying(aTHX)
 #define setfd_cloexec		Perl_setfd_cloexec
-#define setfd_cloexec_for_nonsysfd(a)	Perl_setfd_cloexec_for_nonsysfd(aTHX_ a)
-#define setfd_cloexec_or_inhexec_by_sysfdness(a)	Perl_setfd_cloexec_or_inhexec_by_sysfdness(aTHX_ a)
 #define setfd_inhexec		Perl_setfd_inhexec
 #define setfd_inhexec_for_sysfd(a)	Perl_setfd_inhexec_for_sysfd(aTHX_ a)
 #define sub_crush_depth(a)	Perl_sub_crush_depth(aTHX_ a)
diff --git a/perl.c b/perl.c
index 5c839f3900..d39bb1b466 100644
--- a/perl.c
+++ b/perl.c
@@ -842,7 +842,7 @@ perl_destruct(pTHXx)
 		   back into Perl_debug_log, as if we never actually closed it
 		*/
 		if(got_fd != debug_fd) {
-		    if (PerlLIO_dup2_cloexec(got_fd, debug_fd) == -1) {
+		    if (dup2(got_fd, debug_fd) == -1) {
 			where = "dup2";
 			goto abort;
 		    }
@@ -4075,6 +4075,8 @@ S_open_script(pTHX_ const char *scriptname, bool dosearch, bool *suidscript)
 		    CopFILE(PL_curcop), Strerror(errno));
     }
     fd = PerlIO_fileno(rsfp);
+    if (fd >= 0)
+	setfd_cloexec(fd);
 
     if (fd < 0 ||
         (PerlLIO_fstat(fd, &tmpstatbuf) >= 0
diff --git a/perlio.c b/perlio.c
index f5eb4851b6..fa9f54feda 100644
--- a/perlio.c
+++ b/perlio.c
@@ -245,7 +245,7 @@ PerlIO_fdupopen(pTHX_ PerlIO *f, CLONE_PARAMS *param, int flags)
     return win32_fdupopen(f);
 # else
     if (f) {
-	const int fd = PerlLIO_dup_cloexec(PerlIO_fileno(f));
+	const int fd = PerlLIO_dup(PerlIO_fileno(f));
 	if (fd >= 0) {
 	    char mode[8];
 #  ifdef DJGPP
@@ -289,7 +289,7 @@ PerlIO_openn(pTHX_ const char *layers, const char *mode, int fd,
                 return NULL;
 
 	    if (*mode == IoTYPE_NUMERIC) {
-		fd = PerlLIO_open3_cloexec(name, imode, perm);
+		fd = PerlLIO_open3(name, imode, perm);
 		if (fd >= 0)
 		    return PerlIO_fdopen(fd, mode + 1);
 	    }
@@ -2642,7 +2642,6 @@ PerlIOUnix_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 		IV n, const char *mode, int fd, int imode,
 		int perm, PerlIO *f, int narg, SV **args)
 {
-    bool known_cloexec = 0;
     if (PerlIOValid(f)) {
 	if (PerlIOBase(f)->tab && PerlIOBase(f)->flags & PERLIO_F_OPEN)
 	    (*PerlIOBase(f)->tab->Close)(aTHX_ f);
@@ -2663,15 +2662,10 @@ PerlIOUnix_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 	    const char *path = SvPV_const(*args, len);
 	    if (!IS_SAFE_PATHNAME(path, len, "open"))
                 return NULL;
-	    fd = PerlLIO_open3_cloexec(path, imode, perm);
-	    known_cloexec = 1;
+	    fd = PerlLIO_open3(path, imode, perm);
 	}
     }
     if (fd >= 0) {
-	if (known_cloexec)
-	    setfd_inhexec_for_sysfd(fd);
-	else
-	    setfd_cloexec_or_inhexec_by_sysfdness(fd);
 	if (*mode == IoTYPE_IMPLICIT)
 	    mode++;
 	if (!f) {
@@ -2706,9 +2700,7 @@ PerlIOUnix_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
     const PerlIOUnix * const os = PerlIOSelf(o, PerlIOUnix);
     int fd = os->fd;
     if (flags & PERLIO_DUP_FD) {
-	fd = PerlLIO_dup_cloexec(fd);
-	if (fd >= 0)
-	    setfd_inhexec_for_sysfd(fd);
+	fd = PerlLIO_dup(fd);
     }
     if (fd >= 0) {
 	f = PerlIOBase_dup(aTHX_ f, o, param, flags);
@@ -2972,7 +2964,7 @@ PerlIO_importFILE(FILE *stdio, const char *mode)
 	       Note that the errno value set by a failing fdopen
 	       varies between stdio implementations.
 	     */
-            const int fd = PerlLIO_dup_cloexec(fd0);
+            const int fd = PerlLIO_dup(fd0);
 	    FILE *f2;
             if (fd < 0) {
                 return f;
@@ -2994,12 +2986,11 @@ PerlIO_importFILE(FILE *stdio, const char *mode)
 	if ((f = PerlIO_push(aTHX_(PerlIO_allocate(aTHX)), PERLIO_FUNCS_CAST(&PerlIO_stdio), mode, NULL))) {
 	    s = PerlIOSelf(f, PerlIOStdio);
 	    s->stdio = stdio;
-	    fd0 = fileno(stdio);
-	    if(fd0 != -1){
-		PerlIOUnix_refcnt_inc(fd0);
-		setfd_cloexec_or_inhexec_by_sysfdness(fd0);
-	    }
 #ifdef EBCDIC
+		fd0 = fileno(stdio);
+		if(fd0 != -1){
+			PerlIOUnix_refcnt_inc(fd0);
+		}
 		else{
 			rc = fldata(stdio,filename,&fileinfo);
 			if(rc != 0){
@@ -3010,6 +3001,8 @@ PerlIO_importFILE(FILE *stdio, const char *mode)
 			}
 			  /*This MVS dataset , OK!*/
 		}
+#else
+	    PerlIOUnix_refcnt_inc(fileno(stdio));
 #endif
 	}
     }
@@ -3035,9 +3028,7 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 	if (!s->stdio)
 	    return NULL;
 	s->stdio = stdio;
-	fd = fileno(stdio);
-	PerlIOUnix_refcnt_inc(fd);
-	setfd_cloexec_or_inhexec_by_sysfdness(fd);
+	PerlIOUnix_refcnt_inc(fileno(s->stdio));
 	return f;
     }
     else {
@@ -3048,7 +3039,7 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
                 return NULL;
 	    if (*mode == IoTYPE_NUMERIC) {
 		mode++;
-		fd = PerlLIO_open3_cloexec(path, imode, perm);
+		fd = PerlLIO_open3(path, imode, perm);
 	    }
 	    else {
 	        FILE *stdio;
@@ -3068,9 +3059,7 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 		    f = PerlIO_push(aTHX_ f, self, mode, PerlIOArg);
 		    if (f) {
 			PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
-			fd = fileno(stdio);
-			PerlIOUnix_refcnt_inc(fd);
-			setfd_cloexec_or_inhexec_by_sysfdness(fd);
+			PerlIOUnix_refcnt_inc(fileno(stdio));
 		    } else {
 			PerlSIO_fclose(stdio);
 		    }
@@ -3111,9 +3100,7 @@ PerlIOStdio_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers,
 		}
 		if ((f = PerlIO_push(aTHX_ f, self, mode, PerlIOArg))) {
 		    PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
-		    fd = fileno(stdio);
-		    PerlIOUnix_refcnt_inc(fd);
-		    setfd_cloexec_or_inhexec_by_sysfdness(fd);
+		    PerlIOUnix_refcnt_inc(fileno(stdio));
 		}
 		return f;
 	    }
@@ -3134,7 +3121,7 @@ PerlIOStdio_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
 	const int fd = fileno(stdio);
 	char mode[8];
 	if (flags & PERLIO_DUP_FD) {
-	    const int dfd = PerlLIO_dup_cloexec(fileno(stdio));
+	    const int dfd = PerlLIO_dup(fileno(stdio));
 	    if (dfd >= 0) {
 		stdio = PerlSIO_fdopen(dfd, PerlIO_modestr(o,mode));
 		goto set_this;
@@ -3150,9 +3137,7 @@ PerlIOStdio_dup(pTHX_ PerlIO *f, PerlIO *o, CLONE_PARAMS *param, int flags)
     set_this:
 	PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
         if(stdio) {
-	    int fd = fileno(stdio);
-	    PerlIOUnix_refcnt_inc(fd);
-	    setfd_cloexec_or_inhexec_by_sysfdness(fd);
+	    PerlIOUnix_refcnt_inc(fileno(stdio));
         }
     }
     return f;
@@ -3309,7 +3294,7 @@ PerlIOStdio_close(pTHX_ PerlIO *f)
 	    SAVE_ERRNO;
 	    invalidate = PerlIOStdio_invalidate_fileno(aTHX_ stdio);
 	    if (!invalidate) {
-		dupfd = PerlLIO_dup_cloexec(fd);
+		dupfd = PerlLIO_dup(fd);
 #ifdef USE_ITHREADS
 		if (dupfd < 0) {
 		    /* Oh cXap. This isn't going to go well. Not sure if we can
@@ -3334,8 +3319,7 @@ PerlIOStdio_close(pTHX_ PerlIO *f)
 	result = close(fd);
 #endif
 	if (dupfd >= 0) {
-	    PerlLIO_dup2_cloexec(dupfd, fd);
-	    setfd_inhexec_for_sysfd(fd);
+	    PerlLIO_dup2(dupfd,fd);
 	    PerlLIO_close(dupfd);
 	}
         MUTEX_UNLOCK(&PL_perlio_mutex);
@@ -5055,19 +5039,19 @@ PerlIO_tmpfile(void)
 	 /* if TMPDIR is set and not empty, we try that first */
 	 sv = newSVpv(tmpdir, 0);
 	 sv_catpv(sv, tempname + 4);
-	 fd = Perl_my_mkstemp_cloexec(SvPVX(sv));
+	 fd = Perl_my_mkstemp(SvPVX(sv));
      }
      if (fd < 0) {
 	 SvREFCNT_dec(sv);
 	 sv = NULL;
 	 /* else we try /tmp */
-	 fd = Perl_my_mkstemp_cloexec(tempname);
+	 fd = Perl_my_mkstemp(tempname);
      }
      if (fd < 0) {
          /* Try cwd */
          sv = newSVpvs(".");
          sv_catpv(sv, tempname + 4);
-         fd = Perl_my_mkstemp_cloexec(SvPVX(sv));
+         fd = Perl_my_mkstemp(SvPVX(sv));
      }
      umask(old_umask);
      if (fd >= 0) {
diff --git a/pod/perliol.pod b/pod/perliol.pod
index b70a510aad..55aaf147f7 100644
--- a/pod/perliol.pod
+++ b/pod/perliol.pod
@@ -505,14 +505,6 @@ arguments passed to them, I<n> is the index into that array of the
 layer being called. The macro C<PerlIOArg> will return a (possibly
 C<NULL>) SV * for the argument passed to the layer.
 
-Where a layer opens or takes ownership of a file descriptor, that layer is
-responsible for getting the file descriptor's close-on-exec flag into the
-correct state.  The flag should be clear for a file descriptor numbered
-less than or equal to C<PL_maxsysfd>, and set for any file descriptor
-numbered higher.  For thread safety, when a layer opens a new file
-descriptor it should if possible open it with the close-on-exec flag
-initially set.
-
 The I<mode> string is an "C<fopen()>-like" string which would match
 the regular expression C</^[I#]?[rwa]\+?[bt]?$/>.
 
@@ -533,9 +525,6 @@ If I<fd> not negative then it is the numeric file descriptor I<fd>,
 which will be open in a manner compatible with the supplied mode
 string, the call is thus equivalent to C<PerlIO_fdopen>. In this case
 I<nargs> will be zero.
-The file descriptor may have the close-on-exec flag either set or clear;
-it is the responsibility of the layer that takes ownership of it to get
-the flag into the correct state.
 
 If I<nargs> is greater than zero then it gives the number of arguments
 passed to C<open>, otherwise it will be 1 if for example
diff --git a/pp_sys.c b/pp_sys.c
index 5154b9baa8..1556626484 100644
--- a/pp_sys.c
+++ b/pp_sys.c
@@ -692,6 +692,8 @@ PP(pp_pipe_op)
 
     if (PerlProc_pipe_cloexec(fd) < 0)
 	goto badexit;
+    setfd_inhexec_for_sysfd(fd[0]);
+    setfd_inhexec_for_sysfd(fd[1]);
 
     IoIFP(rstio) = PerlIO_fdopen(fd[0], "r" PIPE_OPEN_MODE);
     IoOFP(wstio) = PerlIO_fdopen(fd[1], "w" PIPE_OPEN_MODE);
@@ -2519,6 +2521,7 @@ PP(pp_socket)
     if (fd < 0) {
 	RETPUSHUNDEF;
     }
+    setfd_inhexec_for_sysfd(fd);
     IoIFP(io) = PerlIO_fdopen(fd, "r" SOCKET_OPEN_MODE); /* stdio gets confused about sockets */
     IoOFP(io) = PerlIO_fdopen(fd, "w" SOCKET_OPEN_MODE);
     IoTYPE(io) = IoTYPE_SOCKET;
@@ -2555,6 +2558,8 @@ PP(pp_sockpair)
     TAINT_PROPER("socketpair");
     if (PerlSock_socketpair_cloexec(domain, type, protocol, fd) < 0)
 	RETPUSHUNDEF;
+    setfd_inhexec_for_sysfd(fd[0]);
+    setfd_inhexec_for_sysfd(fd[1]);
     IoIFP(io1) = PerlIO_fdopen(fd[0], "r" SOCKET_OPEN_MODE);
     IoOFP(io1) = PerlIO_fdopen(fd[0], "w" SOCKET_OPEN_MODE);
     IoTYPE(io1) = IoTYPE_SOCKET;
@@ -2670,6 +2675,7 @@ PP(pp_accept)
 
     if (fd < 0)
 	goto badexit;
+    setfd_inhexec_for_sysfd(fd);
     if (IoIFP(nstio))
 	do_close(ngv, FALSE);
     IoIFP(nstio) = PerlIO_fdopen(fd, "r" SOCKET_OPEN_MODE);
diff --git a/proto.h b/proto.h
index 8e0c669db7..583d1e3a83 100644
--- a/proto.h
+++ b/proto.h
@@ -35,7 +35,9 @@ PERL_CALLCONV UV	NATIVE_TO_NEED(const UV enc, const UV ch)
 #endif
 
 PERL_CALLCONV const char *	Perl_PerlIO_context_layers(pTHX_ const char *mode);
-PERL_CALLCONV int	Perl_PerlLIO_dup2_cloexec(pTHX_ int oldfd, int newfd);
+PERL_CALLCONV int	Perl_PerlLIO_dup2_cloexec(pTHX_ int oldfd, int newfd)
+			__attribute__warn_unused_result__;
+
 PERL_CALLCONV int	Perl_PerlLIO_dup_cloexec(pTHX_ int oldfd)
 			__attribute__warn_unused_result__;
 
@@ -2942,8 +2944,6 @@ PERL_CALLCONV void	Perl_setdefout(pTHX_ GV* gv);
 #define PERL_ARGS_ASSERT_SETDEFOUT	\
 	assert(gv)
 PERL_CALLCONV void	Perl_setfd_cloexec(int fd);
-PERL_CALLCONV void	Perl_setfd_cloexec_for_nonsysfd(pTHX_ int fd);
-PERL_CALLCONV void	Perl_setfd_cloexec_or_inhexec_by_sysfdness(pTHX_ int fd);
 PERL_CALLCONV void	Perl_setfd_inhexec(int fd);
 PERL_CALLCONV void	Perl_setfd_inhexec_for_sysfd(pTHX_ int fd);
 PERL_CALLCONV char*	Perl_setlocale(int category, const char* locale);
diff --git a/toke.c b/toke.c
index 6e2742742a..75249430f0 100644
--- a/toke.c
+++ b/toke.c
@@ -7669,6 +7669,11 @@ Perl_yylex(pTHX)
 		if (!GvIO(gv))
 		    GvIOp(gv) = newIO();
 		IoIFP(GvIOp(gv)) = PL_rsfp;
+		{
+		    const int fd = PerlIO_fileno(PL_rsfp);
+                    if (fd >= 3)
+			setfd_cloexec(fd);
+		}
 		/* Mark this internal pseudo-handle as clean */
 		IoFLAGS(GvIOp(gv)) |= IOf_UNTAINT;
 		if ((PerlIO*)PL_rsfp == PerlIO_stdin())
diff --git a/util.c b/util.c
index 0fc7af6866..31b4f402bb 100644
--- a/util.c
+++ b/util.c
@@ -2238,7 +2238,7 @@ Perl_my_popen_list(pTHX_ const char *mode, int n, SV **args)
 	taint_env();
 	taint_proper("Insecure %s%s", "EXEC");
     }
-    if (PerlProc_pipe_cloexec(p) < 0)
+    if (PerlProc_pipe(p) < 0)
 	return NULL;
     /* Try for another pipe pair for error return */
     if (PerlProc_pipe_cloexec(pp) >= 0)
@@ -2298,7 +2298,7 @@ Perl_my_popen_list(pTHX_ const char *mode, int n, SV **args)
 	PerlLIO_close(pp[1]);
     /* Keep the lower of the two fd numbers */
     if (p[that] < p[This]) {
-	PerlLIO_dup2_cloexec(p[This], p[that]);
+	PerlLIO_dup2(p[This], p[that]);
 	PerlLIO_close(p[This]);
 	p[This] = p[that];
     }
@@ -2378,7 +2378,7 @@ Perl_my_popen(pTHX_ const char *cmd, const char *mode)
 	taint_env();
 	taint_proper("Insecure %s%s", "EXEC");
     }
-    if (PerlProc_pipe_cloexec(p) < 0)
+    if (PerlProc_pipe(p) < 0)
 	return NULL;
     if (doexec && PerlProc_pipe_cloexec(pp) >= 0)
 	did_pipes = 1;
@@ -2450,7 +2450,7 @@ Perl_my_popen(pTHX_ const char *cmd, const char *mode)
     if (did_pipes)
 	PerlLIO_close(pp[1]);
     if (p[that] < p[This]) {
-	PerlLIO_dup2_cloexec(p[This], p[that]);
+	PerlLIO_dup2(p[This], p[that]);
 	PerlLIO_close(p[This]);
 	p[This] = p[that];
     }