[Qemu-devel] [PATCH] win32: Set unbuffered stdout

[Stefan Weil]

Win32 does not support line-buffering, but it allows
unbuffered output.

Unbuffered output is a good approximation. For typical output
statements which usually end with '\n', it's even identical.

Buffered output is unusable for program traces because of
its large delay.

Cc: Blue Swirl <address@hidden>
Signed-off-by: Stefan Weil <address@hidden>
---
 os-win32.c      |    6 ++++++
 qemu-os-win32.h |    3 +--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/os-win32.c b/os-win32.c
index dd46bf4..3c6f50f 100644
--- a/os-win32.c
+++ b/os-win32.c
@@ -221,6 +221,12 @@ char *os_find_datadir(const char *argv0)
     return NULL;
 }
 
+void os_set_line_buffering(void)
+{
+    setbuf(stdout, NULL);
+    setbuf(stderr, NULL);
+}
+
 /*
  * Parse OS specific command line options.
  * return 0 if option handled, -1 otherwise
diff --git a/qemu-os-win32.h b/qemu-os-win32.h
index 2ff9f45..c63778d 100644
--- a/qemu-os-win32.h
+++ b/qemu-os-win32.h
@@ -45,8 +45,7 @@ void os_host_main_loop_wait(int *timeout);
 static inline void os_setup_signal_handling(void) {}
 static inline void os_daemonize(void) {}
 static inline void os_setup_post(void) {}
-/* Win32 doesn't support line-buffering and requires size >= 2 */
-static inline void os_set_line_buffering(void) {}
+void os_set_line_buffering(void);
 static inline void os_set_proc_name(const char *dummy) {}
 
 #if !defined(EPROTONOSUPPORT)
-- 
1.7.1