Buffer size digit in file open mode string.

* streamn.c (struct stdio_handle): New member, buf.
(stdio_stream_destroy): Free the stdio_handle's buf.
(parse_mode): Handle digit character, converting it
to integer value stored in m.buforder.
(set_mode_props): Allocate a buffer and install into
FILE * stream if the mode specifies a buforder.
(make_stdio_stream_common): Initialize buffer to null.

* stream.h (struct stdio_mode): New signed bitfield
member, buforder.
(stdio_mode_init_trivial): Initialize buforder member
to -1.

* txr.1: Documented size order digit.

1 files changed, 2 insertions, 1 deletions

diff --git a/stream.h b/stream.h
index 2474ce13..f0c6433a 100644
--- a/stream.h
+++ b/stream.h
@@ -92,9 +92,10 @@ struct stdio_mode {
   unsigned interactive : 1;
   unsigned unbuf : 1;
   unsigned linebuf : 1;
+  int buforder : 5;
 };
 
-#define stdio_mode_init_trivial(read) { 0, read, 0, 0, 0, 0, 0, 0, 0 }
+#define stdio_mode_init_trivial(read) { 0, read, 0, 0, 0, 0, 0, 0, 0, -1 }
 
 #define std_input (deref(lookup_var_l(nil, stdin_s)))
 #define std_output (deref(lookup_var_l(nil, stdout_s)))