[newlib-cygwin] Cygwin: Define FSCTL_PIPE_FLUSH

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=2f48ddb1ca45055eaeaa61af766653251b575a72

commit 2f48ddb1ca45055eaeaa61af766653251b575a72
Author: Corinna Vinschen <corinna@vinschen.de>
Date:   Wed Mar 7 21:54:46 2018 +0100

    Cygwin: Define FSCTL_PIPE_FLUSH
    
    This fsctl might come in handy at one point...
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/ntdll.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/winsup/cygwin/ntdll.h b/winsup/cygwin/ntdll.h
index b251055..64babef 100644
--- a/winsup/cygwin/ntdll.h
+++ b/winsup/cygwin/ntdll.h
@@ -157,6 +157,7 @@ extern GUID __cygwin_socket_guid;
 #define FILE_VC_VALID_MASK              0x000003ff
 
 /* IOCTL code to impersonate client of named pipe. */
+
 #define FSCTL_PIPE_DISCONNECT	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 1, \
 					 METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define FSCTL_PIPE_LISTEN	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 2, \
@@ -165,6 +166,8 @@ extern GUID __cygwin_socket_guid;
 					 METHOD_BUFFERED, FILE_ANY_ACCESS)
 #define FSCTL_PIPE_IMPERSONATE	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 7, \
 					 METHOD_BUFFERED, FILE_ANY_ACCESS)
+#define FSCTL_PIPE_FLUSH	CTL_CODE(FILE_DEVICE_NAMED_PIPE, 16, \
+					 METHOD_BUFFERED, FILE_WRITE_DATA)
 
 typedef enum _FILE_INFORMATION_CLASS
 {