From 6a8ca29f72bb99475d042e18bce1ad7c0f637ee1 Mon Sep 17 00:00:00 2001
From: simonmar <unknown>
Date: Fri, 5 Nov 1999 15:25:49 +0000
Subject: [PATCH] [project @ 1999-11-05 15:25:49 by simonmar] Handle
 potentially blocking writes (yes, I've seen one :) Or
 rather, its footprint: unfortunately, the error message
 didn't appear because writes to stderr were returning
 EAGAIN etc. etc., see accompanying commit to writeError.c.)

---
 ghc/lib/std/cbits/writeFile.c |   14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/ghc/lib/std/cbits/writeFile.c b/ghc/lib/std/cbits/writeFile.c
index 0b459f3..0c2f78f 100644
--- a/ghc/lib/std/cbits/writeFile.c
+++ b/ghc/lib/std/cbits/writeFile.c
@@ -1,7 +1,7 @@
 /* 
  * (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
  *
- * $Id: writeFile.c,v 1.8 1999/09/16 13:14:43 simonmar Exp $
+ * $Id: writeFile.c,v 1.9 1999/11/05 15:25:49 simonmar Exp $
  *
  * hPutStr Runtime Support
  */
@@ -62,13 +62,19 @@ StgInt bytes;
 #else
 		 write(fo->fd, pBuf, bytes))) < bytes) {
 #endif
-	if (errno != EINTR) {
+        if ( count == -1 && errno == EAGAIN) {
+            errno = 0;
+            return FILEOBJ_BLOCKED_WRITE;
+        }
+	else if ( count == -1 && errno != EINTR ) {
 	    cvtErrno();
 	    stdErrno();
 	    return -1;
 	}
-	bytes -= count;
-	pBuf  += count;
+        else {
+	    bytes -= count;
+	    pBuf  += count;
+        }
     }
     /* Signal that we've emptied the buffer */
     fo->bufWPtr=0;
-- 
1.7.10.4