From 27adc08ba6a09336192b74b50f3e5ddc79df4ca8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?=
 <pclouds@gmail.com>
Date: Tue, 4 May 2021 17:46:32 +0700
Subject: [PATCH] chibi-scheme.1: document -b

It's added in fad9e4ca (don't make stdio nonblocking by default, allow
override with -b, 2017-05-07)
---
 doc/chibi-scheme.1 | 4 ++++
 main.c             | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/doc/chibi-scheme.1 b/doc/chibi-scheme.1
index fd75017d..3ec3689b 100644
--- a/doc/chibi-scheme.1
+++ b/doc/chibi-scheme.1
@@ -225,6 +225,10 @@ Loads the Scheme heap from
 .I image-file
 instead of compiling the init file on the fly.
 This feature is still experimental.
+.TP
+.BI -b
+Makes stdio nonblocking (blocking by default). Only available when
+lightweight threads are enabled.
 
 .SH ENVIRONMENT
 .TP
diff --git a/main.c b/main.c
index c1679ce9..9c59957e 100644
--- a/main.c
+++ b/main.c
@@ -59,6 +59,9 @@ void sexp_usage(int err) {
 #if SEXP_USE_IMAGE_LOADING
          "  -d <file>    - dump an image file and exit\n"
          "  -i <file>    - load an image file\n"
+#endif
+#if SEXP_USE_GREEN_THREADS
+         "  -b           - Make stdio nonblocking\n"
 #endif
          );
   if (err == 0) exit_success();