Index: src/OFHTTPServer.m
==================================================================
--- src/OFHTTPServer.m
+++ src/OFHTTPServer.m
@@ -230,11 +230,11 @@
 
 	if (!_chunked) {
 		@try {
 			[_socket writeBuffer: buffer length: length];
 		} @catch (OFWriteFailedException *e) {
-			if (e.errNo == EWOULDBLOCK)
+			if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 				return e.bytesWritten;
 
 			@throw e;
 		}
 

Index: src/OFLHAArchive.m
==================================================================
--- src/OFLHAArchive.m
+++ src/OFLHAArchive.m
@@ -487,11 +487,11 @@
 		OFEnsure(e.bytesWritten <= length);
 
 		_bytesWritten += (uint32_t)e.bytesWritten;
 		_CRC16 = OFCRC16(_CRC16, buffer, e.bytesWritten);
 
-		if (e.errNo == EWOULDBLOCK)
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return e.bytesWritten;
 
 		@throw e;
 	}
 

Index: src/OFRunLoop.m
==================================================================
--- src/OFRunLoop.m
+++ src/OFRunLoop.m
@@ -573,11 +573,11 @@
 		length = dataLength - _writtenLength;
 		[object writeBuffer: dataItems + _writtenLength length: length];
 	} @catch (OFWriteFailedException *e) {
 		length = e.bytesWritten;
 
-		if (e.errNo != EWOULDBLOCK)
+		if (e.errNo != EWOULDBLOCK && e.errNo != EAGAIN)
 			exception = e;
 	} @catch (id e) {
 		length = 0;
 		exception = e;
 	}
@@ -650,11 +650,11 @@
 		length = cStringLength - _writtenLength;
 		[object writeBuffer: cString + _writtenLength length: length];
 	} @catch (OFWriteFailedException *e) {
 		length = e.bytesWritten;
 
-		if (e.errNo != EWOULDBLOCK)
+		if (e.errNo != EWOULDBLOCK && e.errNo != EAGAIN)
 			exception = e;
 	} @catch (id e) {
 		length = 0;
 		exception = e;
 	}

Index: src/OFStream.h
==================================================================
--- src/OFStream.h
+++ src/OFStream.h
@@ -829,12 +829,14 @@
 /**
  * @brief Writes from a buffer into the stream.
  *
  * In non-blocking mode, if less than the specified length could be written, an
  * @ref OFWriteFailedException is thrown with @ref OFWriteFailedException#errNo
- * being set to `EWOULDBLOCK` and @ref OFWriteFailedException#bytesWritten
- * being set to the number of bytes that were written, if any.
+ * being set to `EWOULDBLOCK` or `EAGAIN` (you need to check for both, as they
+ * are not the same on some systems) and
+ * @ref OFWriteFailedException#bytesWritten being set to the number of bytes
+ * that were written, if any.
  *
  * @param buffer The buffer from which the data is written into the stream
  * @param length The length of the data that should be written
  */
 - (void)writeBuffer: (const void *)buffer length: (size_t)length;

Index: src/OFTarArchive.m
==================================================================
--- src/OFTarArchive.m
+++ src/OFTarArchive.m
@@ -442,11 +442,11 @@
 	} @catch (OFWriteFailedException *e) {
 		OFEnsure(e.bytesWritten <= length);
 
 		_toWrite -= e.bytesWritten;
 
-		if (e.errNo == EWOULDBLOCK)
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return e.bytesWritten;
 
 		@throw e;
 	}
 

Index: src/OFZIPArchive.m
==================================================================
--- src/OFZIPArchive.m
+++ src/OFZIPArchive.m
@@ -897,11 +897,11 @@
 		OFEnsure(e.bytesWritten <= length);
 
 		_bytesWritten += (int64_t)e.bytesWritten;
 		_CRC32 = OFCRC32(_CRC32, buffer, e.bytesWritten);
 
-		if (e.errNo == EWOULDBLOCK)
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return e.bytesWritten;
 
 		@throw e;
 	}
 

Index: src/tls/OFGnuTLSTLSStream.m
==================================================================
--- src/tls/OFGnuTLSTLSStream.m
+++ src/tls/OFGnuTLSTLSStream.m
@@ -48,11 +48,11 @@
 		gnutls_transport_set_errno(stream->_session, e.errNo);
 		return -1;
 	}
 
 	if (length == 0 && !stream.underlyingStream.atEndOfStream) {
-		gnutls_transport_set_errno(stream->_session, EWOULDBLOCK);
+		gnutls_transport_set_errno(stream->_session, EAGAIN);
 		return -1;
 	}
 
 	return length;
 }
@@ -65,11 +65,11 @@
 	@try {
 		[stream.underlyingStream writeBuffer: buffer length: length];
 	} @catch (OFWriteFailedException *e) {
 		gnutls_transport_set_errno(stream->_session, e.errNo);
 
-		if (e.errNo == EWOULDBLOCK)
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return e.bytesWritten;
 
 		return -1;
 	}
 
@@ -146,11 +146,11 @@
 		/*
 		 * The underlying stream might have had data ready, but not
 		 * enough for GnuTLS to return decrypted data. This means the
 		 * caller might have observed the TLS stream for reading, got a
 		 * ready signal and read - and expects the read to succeed, not
-		 * to fail with EWOULDBLOCK, as it was signaled ready.
+		 * to fail with EWOULDBLOCK/EAGAIN, as it was signaled ready.
 		 * Therefore, return 0, as we could read 0 decrypted bytes, but
 		 * cleared the ready signal of the underlying stream.
 		 */
 		if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN)
 			return 0;
@@ -170,20 +170,18 @@
 
 	if (!_handshakeDone)
 		@throw [OFNotOpenException exceptionWithObject: self];
 
 	if ((ret = gnutls_record_send(_session, buffer, length)) < 0) {
-		/* FIXME: Translate error to errNo */
-		int errNo = 0;
-
 		if (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN)
-			errNo = EWOULDBLOCK;
+			return 0;
 
+		/* FIXME: Translate error to errNo */
 		@throw [OFWriteFailedException exceptionWithObject: self
 						   requestedLength: length
 						      bytesWritten: ret
-							     errNo: errNo];
+							     errNo: 0];
 	}
 
 	return ret;
 }
 

Index: src/tls/OFSecureTransportTLSStream.m
==================================================================
--- src/tls/OFSecureTransportTLSStream.m
+++ src/tls/OFSecureTransportTLSStream.m
@@ -36,11 +36,11 @@
 	@try {
 		length = [((OFTLSStream *)connection).underlyingStream
 		    readIntoBuffer: data
 			    length: *dataLength];
 	} @catch (OFReadFailedException *e) {
-		if (e.errNo == EWOULDBLOCK) {
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN) {
 			*dataLength = 0;
 			return errSSLWouldBlock;
 		}
 
 		@throw e;
@@ -60,11 +60,11 @@
 		    writeBuffer: data
 			 length: *dataLength];
 	} @catch (OFWriteFailedException *e) {
 		*dataLength = e.bytesWritten;
 
-		if (e.errNo == EWOULDBLOCK)
+		if (e.errNo == EWOULDBLOCK || e.errNo == EAGAIN)
 			return errSSLWouldBlock;
 
 		@throw e;
 	}