Teach bisect-runner.pl that on HP-UX, _filbuf() is named __filbuf().

This is all that is needed to build 5.003 and earlier. bisect.pl can validate
all stable versions from blead back to 5.002

diff --git a/Porting/bisect-runner.pl b/Porting/bisect-runner.pl
index 57aae49..d0be2e5 100755 (executable)
--- a/Porting/bisect-runner.pl
+++ b/Porting/bisect-runner.pl
@@ -2372,6 +2372,26 @@ EOPATCH
         }
     }
 
+    if ($major < 4 && $^O eq 'hpux'
+        && extract_from_file('sv.c', qr/i = _filbuf\(/)) {
+            apply_patch(<<'EOPATCH');
+diff --git a/sv.c b/sv.c
+index a1f1d60..0a806f1 100644
+--- a/sv.c
++++ b/sv.c
+@@ -2641,7 +2641,7 @@ I32 append;
+ 
+       FILE_cnt(fp) = cnt;             /* deregisterize cnt and ptr */
+       FILE_ptr(fp) = ptr;
+-      i = _filbuf(fp);                /* get more characters */
++      i = __filbuf(fp);               /* get more characters */
+       cnt = FILE_cnt(fp);
+       ptr = FILE_ptr(fp);             /* reregisterize cnt and ptr */
+ 
+
+EOPATCH
+    }
+
     if ($major == 4 && extract_from_file('scope.c', qr/\(SV\*\)SSPOPINT/)) {
         # [PATCH] 5.004_04 +MAINT_TRIAL_1 broken when sizeof(int) != sizeof(void)
         # Fixes a bug introduced in 161b7d1635bc830b