hush: fix fallout from FILE->HFILE conversion

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/shell/hush.c b/shell/hush.c
index 3407711cdd282a04df737b830f20470a25e7abbe..c4b1248259f10a6b64f83b94a40bd966be98c94e 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1683,9 +1683,15 @@ static void close_all_HFILE_list(void)
                 * It is disastrous if we share memory with a vforked parent.
                 * I'm not sure we never come here after vfork.
                 * Therefore just close fd, nothing more.
+                *
+                * ">" instead of ">=": we don't close fd#0,
+                * interactive shell uses hfopen(NULL) as stdin input
+                * which has fl->fd == 0, but fd#0 gets redirected in pipes.
+                * If we'd close it here, then e.g. interactive "set | sort"
+                * with NOFORKed sort, would have sort's input fd closed.
                 */
-               /*hfclose(fl); - unsafe */
-               if (fl->fd >= 0)
+               if (fl->fd > 0)
+                       /*hfclose(fl); - unsafe */
                        close(fl->fd);
                fl = fl->next_hfile;
        }