Purge sfio support, which has been broken for a decade.

The last Perl release that built with -Dusesfio was v5.8.0, and even that
failed many regression tests. Every subsequent release fails to build, and
in the decade that has passed we have had no bug reports about this. So it's
safe to delete all the code. The Configure related code will be purged in a
subsequent commit.

2 references to sfio intentionally remain in fakesdio.h and nostdio.h, as
these appear to be for using its stdio API-compatibility layer.

1 files changed, 3 insertions, 10 deletions

diff --git a/util.c b/util.c
index 26a002abe7..e3059434ba 100644
--- a/util.c
+++ b/util.c
@@ -26,7 +26,7 @@
 #include "perl.h"
 #include "reentr.h"
 
-#if defined(USE_PERLIO) && !defined(USE_SFIO)
+#if defined(USE_PERLIO)
 #include "perliol.h" /* For PerlIOUnix_refcnt */
 #endif
 
@@ -1343,17 +1343,10 @@ Perl_write_to_stderr(pTHX_ SV* msv)
 	Perl_magic_methcall(aTHX_ MUTABLE_SV(io), mg, SV_CONST(PRINT),
 			    G_SCALAR | G_DISCARD | G_WRITING_TO_STDERR, 1, msv);
     else {
-#ifdef USE_SFIO
-	/* SFIO can really mess with your errno */
-	dSAVE_ERRNO;
-#endif
 	PerlIO * const serr = Perl_error_log;
 
 	do_print(msv, serr);
 	(void)PerlIO_flush(serr);
-#ifdef USE_SFIO
-	RESTORE_ERRNO;
-#endif
     }
 }
 
@@ -2728,7 +2721,7 @@ Perl_my_pclose(pTHX_ PerlIO *ptr)
     SvREFCNT_dec(*svp);
     *svp = NULL;
 
-#if defined(USE_PERLIO) && !defined(USE_SFIO)
+#if defined(USE_PERLIO)
     /* Find out whether the refcount is low enough for us to wait for the
        child proc without blocking. */
     should_wait = PerlIOUnix_refcnt(fd) == 1 && pid > 0;
@@ -3317,7 +3310,7 @@ Perl_get_vtbl(pTHX_ int vtbl_id)
 I32
 Perl_my_fflush_all(pTHX)
 {
-#if defined(USE_PERLIO) || defined(FFLUSH_NULL) || defined(USE_SFIO)
+#if defined(USE_PERLIO) || defined(FFLUSH_NULL)
     return PerlIO_flush(NULL);
 #else
 # if defined(HAS__FWALK)