1 files changed, 19 insertions, 2 deletions

diff --git a/src/lib/libcrypto/bio/bss_file.c b/src/lib/libcrypto/bio/bss_file.c
index e4e9df144c..0ca603ee0a 100644
--- a/src/lib/libcrypto/bio/bss_file.c
+++ b/src/lib/libcrypto/bio/bss_file.c
@@ -213,12 +213,29 @@ static long MS_CALLBACK file_ctrl(BIO *b, int cmd, long num, void *ptr)
                 b->shutdown=(int)num&BIO_CLOSE;
                 b->ptr=(char *)ptr;
                 b->init=1;
-#if defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_WINDOWS)
-                /* Set correct text/binary mode */
+#if defined(OPENSSL_SYS_WINDOWS)
                 if (num & BIO_FP_TEXT)
                         _setmode(fileno((FILE *)ptr),_O_TEXT);
                 else
                         _setmode(fileno((FILE *)ptr),_O_BINARY);
+#elif defined(OPENSSL_SYS_MSDOS)
+                {
+                int fd = fileno((FILE*)ptr);
+                /* Set correct text/binary mode */
+                if (num & BIO_FP_TEXT)
+                        _setmode(fd,_O_TEXT);
+                /* Dangerous to set stdin/stdout to raw (unless redirected) */
+                else
+                        {
+                        if (fd == STDIN_FILENO || fd == STDOUT_FILENO)
+                                {
+                                if (isatty(fd) <= 0)
+                                        _setmode(fd,_O_BINARY);
+                                }
+                        else
+                                _setmode(fd,_O_BINARY);
+                        }
+                }
 #elif defined(OPENSSL_SYS_OS2)
                 if (num & BIO_FP_TEXT)
                         setmode(fileno((FILE *)ptr), O_TEXT);