@@ -20,10 +20,11 @@
 
 #import "OFStdIOStream.h"
 #import "OFDate.h"
 #import "OFApplication.h"
 
+#import "OFOutOfRangeException.h"
 #import "OFReadFailedException.h"
 #import "OFWriteFailedException.h"
 
 #import "autorelease.h"
 #import "macros.h"
@@ -92,14 +93,24 @@
 - (size_t)lowlevelReadIntoBuffer: (void*)buffer
 			  length: (size_t)length
 {
 	ssize_t ret;
 
+#ifndef _WIN32
 	if (_fd == -1 || _atEndOfStream ||
 	    (ret = read(_fd, buffer, length)) < 0)
 		@throw [OFReadFailedException exceptionWithObject: self
 						  requestedLength: length];
+#else
+	if (length > UINT_MAX)
+		@throw [OFOutOfRangeException exception];
+
+	if (_fd == -1 || _atEndOfStream ||
+	    (ret = read(_fd, buffer, (unsigned int)length)) < 0)
+		@throw [OFReadFailedException exceptionWithObject: self
+						  requestedLength: length];
+#endif
 
 	if (ret == 0)
 		_atEndOfStream = true;
 
 	return ret;
@@ -106,13 +117,23 @@
 }
 
 - (void)lowlevelWriteBuffer: (const void*)buffer
 		     length: (size_t)length
 {
+#ifndef _WIN32
 	if (_fd == -1 || _atEndOfStream || write(_fd, buffer, length) < length)
 		@throw [OFWriteFailedException exceptionWithObject: self
 						   requestedLength: length];
+#else
+	if (length > UINT_MAX)
+		@throw [OFOutOfRangeException exception];
+
+	if (_fd == -1 || _atEndOfStream ||
+	    write(_fd, buffer, (unsigned int)length) < length)
+		@throw [OFWriteFailedException exceptionWithObject: self
+						   requestedLength: length];
+#endif
 }
 
 - (int)fileDescriptorForReading
 {
 	return _fd;