From 5a583d0e58a97038f5fa3bdfa3c35694f0a18f34 Mon Sep 17 00:00:00 2001
From: Lukas Larsson <lukas@erlang.org>
Date: Wed, 28 Feb 2018 10:04:53 +0100
Subject: kernel: Fix handling of os:cmd option max_size in win

git cherry-pick 75b0f73f72e1783d4ace976cdd2b5f23bdc3ebae
---
 lib/kernel/src/os.erl        | 8 ++++----
 lib/kernel/test/os_SUITE.erl | 4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/kernel/src/os.erl b/lib/kernel/src/os.erl
index dbb28c1210..92ac401b72 100644
--- a/lib/kernel/src/os.erl
+++ b/lib/kernel/src/os.erl
@@ -310,16 +310,16 @@ get_data(Port, MonRef, Eot, Sofar, Size, Max) ->
 	    iolist_to_binary(Sofar)
     end.
 
-eot(_Bs, <<>>, _Size, _Max) ->
+eot(Bs, <<>>, Size, Max) when Size + byte_size(Bs) < Max ->
     more;
+eot(Bs, <<>>, Size, Max) ->
+    binary:part(Bs, {0, Max - Size});
 eot(Bs, Eot, Size, Max) ->
     case binary:match(Bs, Eot) of
-        nomatch when Size + byte_size(Bs) < Max ->
-            more;
         {Pos, _} when Size + Pos < Max ->
             binary:part(Bs,{0, Pos});
         _ ->
-            binary:part(Bs,{0, Max - Size})
+            eot(Bs, <<>>, Size, Max)
     end.
 
 %% When port_close returns we know that all the
diff --git a/lib/kernel/test/os_SUITE.erl b/lib/kernel/test/os_SUITE.erl
index 70752e6ee6..cfd475becf 100644
--- a/lib/kernel/test/os_SUITE.erl
+++ b/lib/kernel/test/os_SUITE.erl
@@ -324,8 +324,8 @@ max_size_command(_Config) ->
     Res32768 = os:cmd("cat /dev/zero", #{ max_size => 32768 }),
     32768 = length(Res32768),
 
-    ResHello = os:cmd("echo hello", #{ max_size => 20 }),
-    6 = length(ResHello).
+    ResHello = string:trim(os:cmd("echo hello", #{ max_size => 20 })),
+    5 = length(ResHello).
 
 %% Test that the os:perf_counter api works as expected
 perf_counter_api(_Config) ->
-- 
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