Line-buffer stderr

* src/sysdep.c (init_standard_fds) [!DOS_NT]:
Use setvbuf to ensure stderr is line-buffered.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/sysdep.c b/src/sysdep.c
index bc88e70dcb4..3396764d5dc 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -242,6 +242,12 @@ init_standard_fds (void)
   force_open (STDIN_FILENO, O_WRONLY);
   force_open (STDOUT_FILENO, O_RDONLY);
   force_open (STDERR_FILENO, O_RDONLY);
+
+  /* Line-buffer stderr.  However, leave stderr unbuffered on
+     MS-Windows, where setvbuf treats _IOLBF like _IOFBF.  */
+#ifndef DOS_NT
+  setvbuf (stderr, NULL, _IOLBF, 0);
+#endif
 }
 
 /* Return the current working directory.  The result should be freed