diff --git a/stio/lib/Makefile.am b/stio/lib/Makefile.am
index 6151634..2b9713b 100644
--- a/stio/lib/Makefile.am
+++ b/stio/lib/Makefile.am
@@ -22,6 +22,8 @@ pkgbindir = $(bindir)
 pkginclude_HEADERS = \
 	stio-cfg.h \
 	stio-cmn.h \
+	stio-pro.h \
+	stio-sck.h \
 	stio-tcp.h \
 	stio-udp.h \
 	stio.h
@@ -30,6 +32,7 @@ pkglib_LTLIBRARIES = libstio.la
 libstio_la_SOURCES = \
 	stio-prv.h \
 	stio.c \
+	stio-pro.c \
 	stio-sck.c \
 	stio-tcp.c \
 	stio-tim.c \
diff --git a/stio/lib/Makefile.in b/stio/lib/Makefile.in
index 6f9f369..afcac3e 100644
--- a/stio/lib/Makefile.in
+++ b/stio/lib/Makefile.in
@@ -129,9 +129,10 @@ LTLIBRARIES = $(pkglib_LTLIBRARIES)
 am__DEPENDENCIES_1 =
 am__DEPENDENCIES_2 = $(am__DEPENDENCIES_1)
 libstio_la_DEPENDENCIES = $(am__DEPENDENCIES_2)
-am_libstio_la_OBJECTS = libstio_la-stio.lo libstio_la-stio-sck.lo \
-	libstio_la-stio-tcp.lo libstio_la-stio-tim.lo \
-	libstio_la-stio-tmr.lo libstio_la-stio-udp.lo
+am_libstio_la_OBJECTS = libstio_la-stio.lo libstio_la-stio-pro.lo \
+	libstio_la-stio-sck.lo libstio_la-stio-tcp.lo \
+	libstio_la-stio-tim.lo libstio_la-stio-tmr.lo \
+	libstio_la-stio-udp.lo
 libstio_la_OBJECTS = $(am_libstio_la_OBJECTS)
 AM_V_lt = $(am__v_lt_@AM_V@)
 am__v_lt_ = $(am__v_lt_@AM_DEFAULT_V@)
@@ -379,6 +380,8 @@ pkgbindir = $(bindir)
 pkginclude_HEADERS = \
 	stio-cfg.h \
 	stio-cmn.h \
+	stio-pro.h \
+	stio-sck.h \
 	stio-tcp.h \
 	stio-udp.h \
 	stio.h
@@ -387,6 +390,7 @@ pkglib_LTLIBRARIES = libstio.la
 libstio_la_SOURCES = \
 	stio-prv.h \
 	stio.c \
+	stio-pro.c \
 	stio-sck.c \
 	stio-tcp.c \
 	stio-tim.c \
@@ -548,6 +552,7 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstio_la-stio-pro.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstio_la-stio-sck.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstio_la-stio-tcp.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstio_la-stio-tim.Plo@am__quote@
@@ -584,6 +589,13 @@ libstio_la-stio.lo: stio.c
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstio_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o libstio_la-stio.lo `test -f 'stio.c' || echo '$(srcdir)/'`stio.c
 
+libstio_la-stio-pro.lo: stio-pro.c
+@am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstio_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstio_la-stio-pro.lo -MD -MP -MF $(DEPDIR)/libstio_la-stio-pro.Tpo -c -o libstio_la-stio-pro.lo `test -f 'stio-pro.c' || echo '$(srcdir)/'`stio-pro.c
+@am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstio_la-stio-pro.Tpo $(DEPDIR)/libstio_la-stio-pro.Plo
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	$(AM_V_CC)source='stio-pro.c' object='libstio_la-stio-pro.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstio_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o libstio_la-stio-pro.lo `test -f 'stio-pro.c' || echo '$(srcdir)/'`stio-pro.c
+
 libstio_la-stio-sck.lo: stio-sck.c
 @am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstio_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstio_la-stio-sck.lo -MD -MP -MF $(DEPDIR)/libstio_la-stio-sck.Tpo -c -o libstio_la-stio-sck.lo `test -f 'stio-sck.c' || echo '$(srcdir)/'`stio-sck.c
 @am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstio_la-stio-sck.Tpo $(DEPDIR)/libstio_la-stio-sck.Plo
diff --git a/stio/lib/main.c b/stio/lib/main.c
index ed80beb..0a1205f 100644
--- a/stio/lib/main.c
+++ b/stio/lib/main.c
@@ -60,7 +60,7 @@ static stio_mmgr_t mmgr =
 	STIO_NULL
 };
 
-static void tcp_on_disconnected (stio_dev_tcp_t* tcp)
+static void tcp_on_disconnect (stio_dev_tcp_t* tcp)
 {
 	if (tcp->state & STIO_DEV_TCP_CONNECTING)
 	{
@@ -83,7 +83,7 @@ static void tcp_on_disconnected (stio_dev_tcp_t* tcp)
 		printf ("TCP DISCONNECTED - THIS MUST NOT HAPPEN (%d)\n", tcp->sck);
 	}
 }
-static int tcp_on_connected (stio_dev_tcp_t* tcp)
+static int tcp_on_connect (stio_dev_tcp_t* tcp)
 {
 
 	if (tcp->state & STIO_DEV_TCP_CONNECTED)
@@ -95,24 +95,24 @@ printf ("device connected to a remote server... .asdfjkasdfkljasdlfkjasdj...\n")
 printf ("device accepted client device... .asdfjkasdfkljasdlfkjasdj...\n");
 	}
 
-	return stio_dev_tcp_send  (tcp, "hello", 5, STIO_NULL);
+	return stio_dev_tcp_write  (tcp, "hello", 5, STIO_NULL);
 }
 
 
-static int tcp_on_sent (stio_dev_tcp_t* tcp, void* sendctx)
+static int tcp_on_write (stio_dev_tcp_t* tcp, void* wrctx)
 {
 	printf (">>> TCP SENT MESSAGE\n");
 	return 0;
 }
 
-static int tcp_on_recv (stio_dev_tcp_t* tcp, const void* buf, stio_len_t len)
+static int tcp_on_read (stio_dev_tcp_t* tcp, const void* buf, stio_len_t len)
 {
 int n;
 static char a ='A';
 char* xxx = malloc (1000000);
 memset (xxx, a++ ,1000000);
-	//return stio_dev_tcp_send  (tcp, "HELLO", 5, STIO_NULL);
-	n = stio_dev_tcp_send  (tcp, xxx, 1000000, STIO_NULL);
+	//return stio_dev_tcp_write  (tcp, "HELLO", 5, STIO_NULL);
+	n = stio_dev_tcp_write  (tcp, xxx, 1000000, STIO_NULL);
 free (xxx);
 return n;
 }
@@ -170,8 +170,8 @@ int main ()
 	sin.sin_family = AF_INET;
 	memset (&tcp_make, 0, STIO_SIZEOF(&tcp_make));
 	memcpy (&tcp_make.addr, &sin, STIO_SIZEOF(sin));
-	tcp_make.on_sent = tcp_on_sent;
-	tcp_make.on_recv = tcp_on_recv;
+	tcp_make.on_write = tcp_on_write;
+	tcp_make.on_read = tcp_on_read;
 	tcp[0] = stio_dev_tcp_make (stio, 0, &tcp_make);
 	if (!tcp[0])
 	{
@@ -189,8 +189,8 @@ int main ()
 	memset (&tcp_conn, 0, STIO_SIZEOF(tcp_conn));
 	memcpy (&tcp_conn.addr, &sin, STIO_SIZEOF(sin));
 	tcp_conn.timeout.sec = 5;
-	tcp_conn.on_connected = tcp_on_connected;
-	tcp_conn.on_disconnected = tcp_on_disconnected;
+	tcp_conn.on_connect = tcp_on_connect;
+	tcp_conn.on_disconnect = tcp_on_disconnect;
 	if (stio_dev_tcp_connect (tcp[0], &tcp_conn) <= -1)
 	{
 		printf ("stio_dev_tcp_connect() failed....\n");
@@ -202,8 +202,8 @@ int main ()
 	sin.sin_port = htons(1234);
 	memset (&tcp_make, 0, STIO_SIZEOF(&tcp_make));
 	memcpy (&tcp_make.addr, &sin, STIO_SIZEOF(sin));
-	tcp_make.on_sent = tcp_on_sent;
-	tcp_make.on_recv = tcp_on_recv;
+	tcp_make.on_write = tcp_on_write;
+	tcp_make.on_read = tcp_on_read;
 
 	tcp[1] = stio_dev_tcp_make (stio, 0, &tcp_make);
 	if (!tcp[1])
@@ -213,8 +213,8 @@ int main ()
 	}
 
 	tcp_lstn.backlogs = 100;
-	tcp_lstn.on_connected = tcp_on_connected;
-	tcp_lstn.on_disconnected = tcp_on_disconnected;
+	tcp_lstn.on_connect = tcp_on_connect;
+	tcp_lstn.on_disconnect = tcp_on_disconnect;
 	if (stio_dev_tcp_listen (tcp[1], &tcp_lstn) <= -1)
 	{
 		printf ("stio_dev_tcp_listen() failed....\n");
diff --git a/stio/lib/stio-pro.c b/stio/lib/stio-pro.c
new file mode 100644
index 0000000..8fadd5c
--- /dev/null
+++ b/stio/lib/stio-pro.c
@@ -0,0 +1,259 @@
+/*
+ * $Id$
+ *
+    Copyright (c) 2015-2016 Chung, Hyung-Hwan. All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAfRRANTIES
+    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "stio-pro.h"
+#include "stio-prv.h"
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+static int pro_make (stio_dev_t* dev, void* ctx)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+	stio_dev_pro_make_t* arg = (stio_dev_pro_make_t*)ctx;
+	stio_syshnd_t hnd[6];
+	int i, minidx = -1, maxidx = -1;
+
+	if (arg->flags & STIO_DEV_PRO_WRITEIN)
+	{
+		if (pipe(&hnd[0]) == -1)
+		{
+			dev->stio->errnum = stio_syserrtoerrnum(errno);
+			goto oops;
+		}
+		minidx = 0; maxidx = 1;
+	}
+
+	if (arg->flags & STIO_DEV_PRO_READOUT)
+	{
+		if (pipe(&hnd[2]) == -1)
+		{
+			dev->stio->errnum = stio_syserrtoerrnum(errno);
+			goto oops;
+		}
+		if (minidx == -1) minidx = 2;
+		maxidx = 3;
+	}
+
+	if (arg->flags & STIO_DEV_PRO_READERR)
+	{
+		if (pipe(&hnd[4]) == -1)
+		{
+			dev->stio->errnum = stio_syserrtoerrnum(errno);
+			goto oops;
+		}
+		if (minidx == -1) minidx = 4;
+		maxidx = 5;
+	}
+
+	if (maxidx == -1)
+	{
+		dev->stio->errnum = STIO_EINVAL;
+		goto oops;
+	}
+
+	/* TODO: fork and exec... */
+
+	if (arg->flags & STIO_DEV_PRO_WRITEIN)
+	{
+		/*
+		 * 012345
+		 * rw----
+		 * X
+		 * WRITE => 1
+		 */
+		close (hnd[0]);
+		hnd[0] = STIO_SYSHND_INVALID;
+	}
+
+	if (arg->flags & STIO_DEV_PRO_READOUT)
+	{
+		/*
+		 * 012345
+		 * --rw--
+		 *    X
+		 * READ => 2
+		 */
+		close (hnd[3]);
+		hnd[3] = STIO_SYSHND_INVALID;
+	}
+
+	if (arg->flags & STIO_DEV_PRO_READERR)
+	{
+		/*
+		 * 012345
+		 * ----rw
+		 *      X
+		 * READ => 4
+		 */
+		close (hnd[5]);
+		hnd[5] = STIO_SYSHND_INVALID;
+	}
+
+	if (stio_makesyshndasync (pro->stio, hnd[1]) <= -1 ||
+	    stio_makesyshndasync (pro->stio, hnd[2]) <= -1 ||
+	    stio_makesyshndasync (pro->stio, hnd[4]) <= -1) goto oops;
+
+	return 0;
+
+oops:
+	for (i = minidx; i < maxidx; i++)
+	{
+		if (hnd[i] != STIO_SYSHND_INVALID) close (hnd[i]);
+	}
+
+	return -1;
+}
+
+
+static void pro_kill (stio_dev_t* dev)
+{
+}
+
+static int pro_read (stio_dev_t* dev, void* buf, stio_len_t* len)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+	ssize_t x;
+
+	x = write (pro->pfd, buf, *len);
+	if (x <= -1)
+	{
+		if (errno == EINPROGRESS || errno == EWOULDBLOCK) return 0;  /* no data available */
+		if (errno == EINTR) return 0;
+		pro->stio->errnum = stio_syserrtoerrnum(errno);
+		return -1;
+	}
+
+	*len = x;
+	return 1;
+}
+
+static int pro_write (stio_dev_t* dev, const void* data, stio_len_t* len)
+{
+}
+
+static stio_syshnd_t pro_getsyshnd (stio_dev_t* dev)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+	return (stio_syshnd_t)pro->pfd;
+}
+
+
+static int pro_ioctl (stio_dev_t* dev, int cmd, void* arg)
+{
+	return 0;
+}
+
+static stio_dev_mth_t pro_mth = 
+{
+	pro_make,
+	pro_kill,
+	pro_getsyshnd,
+	pro_read,
+	pro_write,
+	pro_ioctl
+};
+
+static int pro_ready (stio_dev_t* dev, int events)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+printf ("PRO READY...%p\n", dev);
+
+	if (events & STIO_DEV_EVENT_ERR)
+	{
+		pro->stio->errnum = STIO_EDEVERR;
+		return -1;
+	}
+
+	if (events & STIO_DEV_EVENT_HUP)
+	{
+		if (events & (STIO_DEV_EVENT_PRI | STIO_DEV_EVENT_IN | STIO_DEV_EVENT_OUT)) 
+		{
+			/* probably half-open? */
+			return 1;
+		}
+
+		pro->stio->errnum = STIO_EDEVHUP;
+		return -1;
+	}
+
+	return 1; /* the device is ok. carry on reading or writing */
+}
+
+static int pro_on_read (stio_dev_t* dev, const void* data, stio_len_t len)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+	return pro->on_read (pro, data, len);
+}
+
+static int pro_on_write (stio_dev_t* dev, void* wrctx)
+{
+	stio_dev_pro_t* pro = (stio_dev_pro_t*)dev;
+	return pro->on_write (pro, wrctx);
+}
+
+static stio_dev_evcb_t pro_evcb =
+{
+	pro_ready,
+	pro_on_read,
+	pro_on_write
+};
+
+stio_dev_pro_t* stio_dev_pro_make (stio_t* stio, stio_size_t xtnsize, const stio_dev_pro_make_t* data)
+{
+	return (stio_dev_pro_t*)stio_makedev (stio, STIO_SIZEOF(stio_dev_pro_t) + xtnsize, &pro_mth, &pro_evcb, (void*)data);
+}
+
+void stio_dev_pro_kill (stio_dev_pro_t* pro)
+{
+	stio_killdev (pro->stio, (stio_dev_t*)pro);
+}
+
+int stio_dev_pro_write (stio_dev_pro_t* pro, const void* data, stio_len_t len, void* wrctx)
+{
+	return stio_dev_write ((stio_dev_t*)pro, data, len, wrctx);
+}
+
+#if 0
+stio_dev_pro_t* stio_dev_pro_getdev (stio_dev_pro_t* pro, stio_dev_pro_type_t type)
+{
+	switch (type)
+	{
+		case STIO_DEV_PRO_IN:
+			return XXX;
+
+		case STIO_DEV_PRO_OUT:
+			return XXX;
+
+		case STIO_DEV_PRO_ERR:
+			return XXX;
+	}
+
+	pro->dev->stio = STIO_EINVAL;
+	return STIO_NULL;
+}
+#endif
diff --git a/stio/lib/stio-pro.h b/stio/lib/stio-pro.h
new file mode 100644
index 0000000..f52837c
--- /dev/null
+++ b/stio/lib/stio-pro.h
@@ -0,0 +1,111 @@
+/*
+ * $Id$
+ *
+    Copyright (c) 2015-2016 Chung, Hyung-Hwan. All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAfRRANTIES
+    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _STIO_PRO_H_
+#define _STIO_PRO_H_
+
+#include <stio.h>
+
+enum stio_dev_pro_type_t
+{
+	STIO_DEV_PRO_IN,
+	STIO_DEV_PRO_OUT,
+	STIO_DEV_PRO_ERR,
+};
+typedef enum stio_dev_pro_type_t stio_dev_pro_type_t;
+
+
+typedef struct stio_dev_pro_t stio_dev_pro_t;
+
+typedef int (*stio_dev_pro_on_read_t) (stio_dev_pro_t* dev, const void* data, stio_len_t len);
+typedef int (*stio_dev_pro_on_write_t) (stio_dev_pro_t* dev, void* wrctx);
+
+struct stio_dev_pro_t
+{
+	STIO_DEV_HEADERS;
+
+	stio_syshnd_t pfd;
+
+	/* bitwised-ORed of #stio_dev_pro_state_t enumerators */
+	stio_dev_pro_type_t type;
+
+	stio_dev_pro_t* sibling[2];
+
+	stio_dev_pro_on_read_t on_read;
+	stio_dev_pro_on_write_t on_write;
+
+	stio_tmridx_t tmridx_connect;
+};
+
+enum stio_dev_pro_make_flag_t
+{
+	STIO_DEV_PRO_WRITEIN  = (1 << 0),
+	STIO_DEV_PRO_READOUT  = (1 << 1),
+	STIO_DEV_PRO_READERR  = (1 << 2),
+	STIO_DEV_PRO_INTONUL  = (1 << 3),
+	STIO_DEV_PRO_OUTTONUL = (1 << 4),
+	STIO_DEV_PRO_ERRTONUL = (1 << 5),
+	STUO_DEV_PRO_DROPIN   = (1 << 6),
+	STUO_DEV_PRO_DROPOUT  = (1 << 7),
+	STUO_DEV_PRO_DROPERR  = (1 << 8)
+};
+typedef enum stio_dev_pro_make_flag_t stio_dev_pro_make_flag_t;
+
+typedef struct stio_dev_pro_make_t stio_dev_pro_make_t;
+struct stio_dev_pro_make_t
+{
+	int flags; /**< bitwise-ORed of stio_dev_pro_make_flag_t enumerators */
+	const void* cmd;
+	stio_dev_pro_on_write_t on_write;
+	stio_dev_pro_on_read_t on_read;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+STIO_EXPORT  stio_dev_pro_t* stio_dev_pro_make (
+	stio_t*                    stio,
+	stio_size_t                xtnsize,
+	const stio_dev_pro_make_t* data
+);
+
+STIO_EXPORT void stio_dev_pro_kill (
+	stio_dev_pro_t* pro
+);
+
+STIO_EXPORT int stio_dev_pro_write (
+	stio_dev_pro_t*  pro,
+	const void*      data,
+	stio_len_t       len,
+	void*            wrctx
+);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/stio/lib/stio-prv.h b/stio/lib/stio-prv.h
index c3e09fe..72ca2ff 100644
--- a/stio/lib/stio-prv.h
+++ b/stio/lib/stio-prv.h
@@ -157,14 +157,14 @@ struct stio_t
 extern "C" {
 #endif
 
-stio_errnum_t stio_syserrtoerrnum (int no);
-
-stio_sckhnd_t stio_openasyncsck (int domain, int type);
-void stio_closeasyncsck (stio_sckhnd_t sck);
-int stio_makesckasync (stio_sckhnd_t sck);
-
-int stio_getsckadrinfo (stio_t* stio, const stio_sckadr_t* addr, stio_scklen_t* len, stio_sckfam_t* family);
+int stio_makesyshndasync (
+	stio_t*       stio,
+	stio_syshnd_t hnd
+);
 
+stio_errnum_t stio_syserrtoerrnum (
+	int no
+);
 
 
 /**
diff --git a/stio/lib/stio-sck.c b/stio/lib/stio-sck.c
index c36551f..14a4a2f 100644
--- a/stio/lib/stio-sck.c
+++ b/stio/lib/stio-sck.c
@@ -25,7 +25,9 @@
  */
 
 
+#include "stio-sck.h"
 #include "stio-prv.h"
+
 #include <sys/socket.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -34,7 +36,7 @@
 #include <arpa/inet.h>
 
 /* ------------------------------------------------------------------------ */
-void stio_closeasyncsck (stio_sckhnd_t sck)
+void stio_closeasyncsck (stio_t* stio, stio_sckhnd_t sck)
 {
 #if defined(_WIN32)
 	closesocket (sck);
@@ -43,21 +45,12 @@ void stio_closeasyncsck (stio_sckhnd_t sck)
 #endif
 }
 
-int stio_makesckasync (stio_sckhnd_t sck)
+int stio_makesckasync (stio_t* stio, stio_sckhnd_t sck)
 {
-	int flags;
-
-	if ((flags = fcntl (sck, F_GETFL)) <= -1 ||
-	    (flags = fcntl (sck, F_SETFL, flags | O_NONBLOCK)) <= -1)
-	{
-		/* stio_seterrnum (dev->stio, STIO_ESYSERR); or translate errno to stio errnum */
-		return -1;
-	}
-
-	return 0;
+	return stio_makesyshndasync (stio, (stio_syshnd_t)sck);
 }
 
-stio_sckhnd_t stio_openasyncsck (int domain, int type)
+stio_sckhnd_t stio_openasyncsck (stio_t* stio, int domain, int type)
 {
 	stio_sckhnd_t sck;
 
@@ -76,7 +69,7 @@ stio_sckhnd_t stio_openasyncsck (int domain, int type)
 		return STIO_SCKHND_INVALID;
 	}
 
-	if (stio_makesckasync (sck) <= -1)
+	if (stio_makesckasync (stio, sck) <= -1)
 	{
 		close (sck);
 		return STIO_SCKHND_INVALID;
diff --git a/stio/lib/stio-sck.h b/stio/lib/stio-sck.h
new file mode 100644
index 0000000..58318a6
--- /dev/null
+++ b/stio/lib/stio-sck.h
@@ -0,0 +1,109 @@
+/*
+ * $Id$
+ *
+    Copyright (c) 2015-2016 Chung, Hyung-Hwan. All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAfRRANTIES
+    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _STIO_SCK_H_
+#define _STIO_SCK_H_
+
+#include <stio.h>
+
+struct stio_sckadr_t
+{
+	int family;
+	stio_uint8_t data[128]; /* TODO: use the actual sockaddr size */
+};
+
+typedef struct stio_sckadr_t stio_sckadr_t;
+
+#if (STIO_SIZEOF_SOCKLEN_T == STIO_SIZEOF_INT)
+	#if defined(STIO_SOCKLEN_T_IS_SIGNED)
+		typedef int stio_scklen_t;
+	#else
+		typedef unsigned int stio_scklen_t;
+	#endif
+#elif (STIO_SIZEOF_SOCKLEN_T == STIO_SIZEOF_LONG)
+	#if defined(STIO_SOCKLEN_T_IS_SIGNED)
+		typedef long stio_scklen_t;
+	#else
+		typedef unsigned long stio_scklen_t;
+	#endif
+#else
+	typedef int stio_scklen_t;
+#endif
+
+#if defined(_WIN32)
+#	define STIO_IOCP_KEY 1
+	/*
+	typedef HANDLE stio_syshnd_t;
+	typedef SOCKET stio_sckhnd_t;
+#	define STIO_SCKHND_INVALID (INVALID_SOCKET)
+	*/
+
+	typedef stio_uintptr_t qse_sckhnd_t;
+#	define STIO_SCKHND_INVALID (~(qse_sck_hnd_t)0)
+
+#else
+	typedef int stio_sckhnd_t;
+#	define STIO_SCKHND_INVALID (-1)
+	
+#endif
+
+typedef int stio_sckfam_t;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+STIO_EXPORT stio_sckhnd_t stio_openasyncsck (
+	stio_t* stio,
+	int     domain, 
+	int     type
+);
+
+STIO_EXPORT void stio_closeasyncsck (
+	stio_t*       stio,
+	stio_sckhnd_t sck
+);
+
+STIO_EXPORT int stio_makesckasync (
+	stio_t*       stio,
+	stio_sckhnd_t sck
+);
+
+STIO_EXPORT int stio_getsckadrinfo (
+	stio_t*              stio,
+	const stio_sckadr_t* addr,
+	stio_scklen_t*       len,
+	stio_sckfam_t*       family
+);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif
diff --git a/stio/lib/stio-tcp.c b/stio/lib/stio-tcp.c
index 2fda05f..bacb099 100644
--- a/stio/lib/stio-tcp.c
+++ b/stio/lib/stio-tcp.c
@@ -25,8 +25,8 @@
  */
 
 
-#include "stio-prv.h"
 #include "stio-tcp.h"
+#include "stio-prv.h"
 
 #include <unistd.h>
 #include <sys/socket.h>
@@ -36,8 +36,6 @@
 
 static int tcp_make (stio_dev_t* dev, void* ctx)
 {
-/* NOTE: this can be extended to use ctx to tell between INET and INET6 or other types of sockets without creating a new dev method set. */
-
 	stio_dev_tcp_t* tcp = (stio_dev_tcp_t*)dev;
 	stio_dev_tcp_make_t* arg = (stio_dev_tcp_make_t*)ctx;
 	stio_scklen_t len;
@@ -46,7 +44,7 @@ static int tcp_make (stio_dev_t* dev, void* ctx)
 
 	if (stio_getsckadrinfo(dev->stio, &arg->addr, &len, &family) <= -1) return -1;
 
-	tcp->sck = stio_openasyncsck (family, SOCK_STREAM);
+	tcp->sck = stio_openasyncsck (dev->stio, family, SOCK_STREAM);
 	if (tcp->sck == STIO_SCKHND_INVALID) goto oops;
 
 	//setsockopt (udp->sck, SOL_SOCKET, SO_REUSEADDR, ...);
@@ -59,15 +57,15 @@ static int tcp_make (stio_dev_t* dev, void* ctx)
 		goto oops;
 	}
 
-	tcp->on_sent = arg->on_sent;
-	tcp->on_recv = arg->on_recv; 
+	tcp->on_write = arg->on_write;
+	tcp->on_read = arg->on_read; 
 	tcp->tmridx_connect = STIO_TMRIDX_INVALID;
 	return 0;
 
 oops:
 	if (tcp->sck != STIO_SCKHND_INVALID)
 	{
-		stio_closeasyncsck (tcp->sck);
+		stio_closeasyncsck (tcp->stio, tcp->sck);
 		tcp->sck = STIO_SCKHND_INVALID;
 	}
 	return -1;
@@ -79,7 +77,7 @@ static int tcp_make_accepted (stio_dev_t* dev, void* ctx)
 	stio_syshnd_t* sck = (stio_syshnd_t*)ctx;
 
 	tcp->sck = *sck;
-	if (stio_makesckasync (tcp->sck) <= -1) return -1;
+	if (stio_makesckasync (dev->stio, tcp->sck) <= -1) return -1;
 
 	return 0;
 }
@@ -90,7 +88,7 @@ static void tcp_kill (stio_dev_t* dev)
 
 	if (tcp->state & (STIO_DEV_TCP_ACCEPTED | STIO_DEV_TCP_CONNECTED | STIO_DEV_TCP_CONNECTING | STIO_DEV_TCP_LISTENING))
 	{
-		if (tcp->on_disconnected) tcp->on_disconnected (tcp);
+		if (tcp->on_disconnect) tcp->on_disconnect (tcp);
 	}
 
 	if (tcp->tmridx_connect != STIO_TMRIDX_INVALID)
@@ -101,7 +99,7 @@ static void tcp_kill (stio_dev_t* dev)
 
 	if (tcp->sck != STIO_SCKHND_INVALID) 
 	{
-		stio_closeasyncsck (tcp->sck);
+		stio_closeasyncsck (tcp->stio, tcp->sck);
 		tcp->sck = STIO_SCKHND_INVALID;
 	}
 }
@@ -113,7 +111,7 @@ static stio_syshnd_t tcp_getsyshnd (stio_dev_t* dev)
 }
 
 
-static int tcp_recv (stio_dev_t* dev, void* buf, stio_len_t* len)
+static int tcp_read (stio_dev_t* dev, void* buf, stio_len_t* len)
 {
 	stio_dev_tcp_t* tcp = (stio_dev_tcp_t*)dev;
 	ssize_t x;
@@ -131,7 +129,7 @@ static int tcp_recv (stio_dev_t* dev, void* buf, stio_len_t* len)
 	return 1;
 }
 
-static int tcp_send (stio_dev_t* dev, const void* data, stio_len_t* len)
+static int tcp_write (stio_dev_t* dev, const void* data, stio_len_t* len)
 {
 	stio_dev_tcp_t* tcp = (stio_dev_tcp_t*)dev;
 	ssize_t x;
@@ -266,8 +264,8 @@ static int tcp_ioctl (stio_dev_t* dev, int cmd, void* arg)
 
 						tcp->state |= STIO_DEV_TCP_CONNECTING;
 						tcp->peer = conn->addr;
-						tcp->on_connected = conn->on_connected;
-						tcp->on_disconnected = conn->on_disconnected;
+						tcp->on_connect = conn->on_connect;
+						tcp->on_disconnect = conn->on_disconnect;
 						return 0;
 					}
 				}
@@ -279,8 +277,8 @@ static int tcp_ioctl (stio_dev_t* dev, int cmd, void* arg)
 			/* connected immediately */
 			tcp->state |= STIO_DEV_TCP_CONNECTED;
 			tcp->peer = conn->addr;
-			tcp->on_connected = conn->on_connected;
-			tcp->on_disconnected = conn->on_disconnected;
+			tcp->on_connect = conn->on_connect;
+			tcp->on_disconnect = conn->on_disconnect;
 			return 0;
 		#endif
 		}
@@ -301,8 +299,8 @@ static int tcp_ioctl (stio_dev_t* dev, int cmd, void* arg)
 			}
 
 			tcp->state |= STIO_DEV_TCP_LISTENING;
-			tcp->on_connected = lstn->on_connected;
-			tcp->on_disconnected = lstn->on_disconnected;
+			tcp->on_connect = lstn->on_connect;
+			tcp->on_disconnect = lstn->on_disconnect;
 			return 0;
 		#endif
 		}
@@ -317,9 +315,9 @@ static stio_dev_mth_t tcp_mth =
 	tcp_make,
 	tcp_kill,
 	tcp_getsyshnd,
+	tcp_read,
+	tcp_write,
 	tcp_ioctl, 
-	tcp_recv,
-	tcp_send
 };
 
 /* accepted tcp socket */
@@ -328,9 +326,9 @@ static stio_dev_mth_t tcp_acc_mth =
 	tcp_make_accepted,
 	tcp_kill,
 	tcp_getsyshnd,
-	tcp_ioctl, 
-	tcp_recv,
-	tcp_send
+	tcp_read,
+	tcp_write,
+	tcp_ioctl
 };
 
 /* ------------------------------------------------------------------------ */
@@ -405,7 +403,7 @@ printf ("CAANOT MANIPULTE WATCHER ...\n");
 					STIO_ASSERT (tcp->tmridx_connect == STIO_TMRIDX_INVALID);
 				}
 
-				if (tcp->on_connected (tcp) <= -1) 
+				if (tcp->on_connect (tcp) <= -1) 
 				{
 					printf ("ON_CONNECTE HANDLER RETURNEF FAILURE...\n");
 					return -1;
@@ -422,7 +420,7 @@ printf ("CAANOT MANIPULTE WATCHER ...\n");
 			}
 		}
 
-		return 0; /* success but don't invoke on_recv() */ 
+		return 0; /* success but don't invoke on_read() */ 
 	}
 	else if (tcp->state & STIO_DEV_TCP_LISTENING)
 	{
@@ -448,7 +446,7 @@ printf ("CAANOT MANIPULTE WATCHER ...\n");
 
 			addrlen = STIO_SIZEOF(peer);
 			clisck = accept (tcp->sck, (struct sockaddr*)&peer, &addrlen);
-			if (clisck == -1)
+			if (clisck == STIO_SCKHND_INVALID)
 			{
 				if (errno == EINPROGRESS || errno == EWOULDBLOCK) return 0;
 				if (errno == EINTR) return 0; /* if interrupted by a signal, treat it as if it's EINPROGRESS */
@@ -472,15 +470,15 @@ printf ("CAANOT MANIPULTE WATCHER ...\n");
 
 
 			/* inherit some event handlers from the parent.
-			 * you can still change them inside the on_connected handler */
-			clitcp->on_connected = tcp->on_connected;
-			clitcp->on_disconnected = tcp->on_disconnected; 
-			clitcp->on_sent = tcp->on_sent;
-			clitcp->on_recv = tcp->on_recv;
+			 * you can still change them inside the on_connect handler */
+			clitcp->on_connect = tcp->on_connect;
+			clitcp->on_disconnect = tcp->on_disconnect; 
+			clitcp->on_write = tcp->on_write;
+			clitcp->on_read = tcp->on_read;
 
 			clitcp->tmridx_connect = STIO_TMRIDX_INVALID;
-			if (clitcp->on_connected (clitcp) <= -1) stio_dev_tcp_kill (clitcp);
-			return 0; /* success but don't invoke on_recv() */ 
+			if (clitcp->on_connect (clitcp) <= -1) stio_dev_tcp_kill (clitcp);
+			return 0; /* success but don't invoke on_read() */ 
 		}
 	}
 	else if (events & STIO_DEV_EVENT_HUP)
@@ -498,23 +496,23 @@ printf ("CAANOT MANIPULTE WATCHER ...\n");
 	return 1; /* the device is ok. carry on reading or writing */
 }
 
-static int tcp_on_recv (stio_dev_t* dev, const void* data, stio_len_t len)
+static int tcp_on_read (stio_dev_t* dev, const void* data, stio_len_t len)
 {
 	stio_dev_tcp_t* tcp = (stio_dev_tcp_t*)dev;
-	return tcp->on_recv (tcp, data, len);
+	return tcp->on_read (tcp, data, len);
 }
 
-static int tcp_on_sent (stio_dev_t* dev, void* sendctx)
+static int tcp_on_write (stio_dev_t* dev, void* wrctx)
 {
 	stio_dev_tcp_t* tcp = (stio_dev_tcp_t*)dev;
-	return tcp->on_sent (tcp, sendctx);
+	return tcp->on_write (tcp, wrctx);
 }
 
 static stio_dev_evcb_t tcp_evcb =
 {
 	tcp_ready,
-	tcp_on_recv,
-	tcp_on_sent
+	tcp_on_read,
+	tcp_on_write
 };
 
 stio_dev_tcp_t* stio_dev_tcp_make (stio_t* stio, stio_size_t xtnsize, const stio_dev_tcp_make_t* data)
@@ -542,7 +540,7 @@ int stio_dev_tcp_listen (stio_dev_tcp_t* tcp, stio_dev_tcp_listen_t* lstn)
 	return stio_dev_ioctl ((stio_dev_t*)tcp, STIO_DEV_TCP_LISTEN, lstn);
 }
 
-int stio_dev_tcp_send (stio_dev_tcp_t* tcp, const void* data, stio_len_t len, void* sendctx)
+int stio_dev_tcp_write (stio_dev_tcp_t* tcp, const void* data, stio_len_t len, void* wrctx)
 {
-	return stio_dev_send ((stio_dev_t*)tcp, data, len, sendctx);
+	return stio_dev_write ((stio_dev_t*)tcp, data, len, wrctx);
 }
diff --git a/stio/lib/stio-tcp.h b/stio/lib/stio-tcp.h
index 83fdaef..cc73fa7 100644
--- a/stio/lib/stio-tcp.h
+++ b/stio/lib/stio-tcp.h
@@ -28,6 +28,7 @@
 #define _STIO_TCP_H_
 
 #include <stio.h>
+#include <stio-sck.h>
 
 enum stio_dev_tcp_ioctl_cmd_t
 {
@@ -48,12 +49,12 @@ typedef enum stio_dev_tcp_state_t stio_dev_tcp_state_t;
 
 typedef struct stio_dev_tcp_t stio_dev_tcp_t;
 
-typedef int (*stio_dev_tcp_on_connected_t) (stio_dev_tcp_t* dev);
+typedef int (*stio_dev_tcp_on_connect_t) (stio_dev_tcp_t* dev);
 typedef void (*stio_dev_tcp_on_accepted_t) (stio_dev_tcp_t* dev, stio_dev_tcp_t* clidev);
-typedef void (*stio_dev_tcp_on_disconnected_t) (stio_dev_tcp_t* dev);
+typedef void (*stio_dev_tcp_on_disconnect_t) (stio_dev_tcp_t* dev);
 
-typedef int (*stio_dev_tcp_on_recv_t) (stio_dev_tcp_t* dev, const void* data, stio_len_t len);
-typedef int (*stio_dev_tcp_on_sent_t) (stio_dev_tcp_t* dev, void* sendctx);
+typedef int (*stio_dev_tcp_on_read_t) (stio_dev_tcp_t* dev, const void* data, stio_len_t len);
+typedef int (*stio_dev_tcp_on_write_t) (stio_dev_tcp_t* dev, void* wrctx);
 
 struct stio_dev_tcp_t
 {
@@ -70,17 +71,14 @@ struct stio_dev_tcp_t
 	 *  STIO_DEV_TCP_CONNECTING */
 	stio_sckadr_t peer;
 
-	/* parent tcp device. valid if STIO_DEV_TCP_ACCEPTED is set */
-	/*stio_dev_tcp_t* parent;*/
-
 	/** return 0 on succes, -1 on failure/
 	 *  called on a new tcp device for an accepted client or
 	 *         on a tcp device conntected to a remote server */
-	stio_dev_tcp_on_connected_t on_connected;
+	stio_dev_tcp_on_connect_t on_connect;
 
-	stio_dev_tcp_on_disconnected_t on_disconnected;
-	stio_dev_tcp_on_recv_t on_recv;
-	stio_dev_tcp_on_sent_t on_sent;
+	stio_dev_tcp_on_disconnect_t on_disconnect;
+	stio_dev_tcp_on_read_t on_read;
+	stio_dev_tcp_on_write_t on_write;
 
 	stio_tmridx_t tmridx_connect;
 };
@@ -90,8 +88,8 @@ struct stio_dev_tcp_make_t
 {
 	/* TODO: options: REUSEADDR for binding?? */
 	stio_sckadr_t addr; /* binding address. */
-	stio_dev_tcp_on_sent_t on_sent;
-	stio_dev_tcp_on_recv_t on_recv;
+	stio_dev_tcp_on_write_t on_write;
+	stio_dev_tcp_on_read_t on_read;
 };
 
 typedef struct stio_dev_tcp_bind_t stio_dev_tcp_bind_t;
@@ -107,16 +105,16 @@ struct stio_dev_tcp_connect_t
 {
 	stio_sckadr_t addr;
 	stio_ntime_t timeout; /* connect timeout */
-	stio_dev_tcp_on_connected_t on_connected;
-	stio_dev_tcp_on_disconnected_t on_disconnected;
+	stio_dev_tcp_on_connect_t on_connect;
+	stio_dev_tcp_on_disconnect_t on_disconnect;
 };
 
 typedef struct stio_dev_tcp_listen_t stio_dev_tcp_listen_t;
 struct stio_dev_tcp_listen_t
 {
 	int backlogs;
-	stio_dev_tcp_on_connected_t on_connected; /* optional, but new connections are dropped immediately without this */
-	stio_dev_tcp_on_disconnected_t on_disconnected; /* should on_discconneted be part of on_accept_t??? */
+	stio_dev_tcp_on_connect_t on_connect; /* optional, but new connections are dropped immediately without this */
+	stio_dev_tcp_on_disconnect_t on_disconnect; /* should on_discconneted be part of on_accept_t??? */
 };
 
 typedef struct stio_dev_tcp_accept_t stio_dev_tcp_accept_t;
@@ -124,7 +122,6 @@ struct stio_dev_tcp_accept_t
 {
 	stio_syshnd_t   sck;
 /* TODO: add timeout */
-	/*stio_dev_tcp_t* parent;*/
 	stio_sckadr_t   peer;
 };
 
@@ -156,11 +153,11 @@ STIO_EXPORT int stio_dev_tcp_listen (
 	stio_dev_tcp_listen_t*  lstn
 );
 
-STIO_EXPORT int stio_dev_tcp_send (
+STIO_EXPORT int stio_dev_tcp_write (
 	stio_dev_tcp_t*  tcp,
 	const void*      data,
 	stio_len_t       len,
-	void*            sendctx
+	void*            wrctx
 );
 
 #ifdef __cplusplus
diff --git a/stio/lib/stio-udp.c b/stio/lib/stio-udp.c
index 096ebe3..8732514 100644
--- a/stio/lib/stio-udp.c
+++ b/stio/lib/stio-udp.c
@@ -25,8 +25,8 @@
  */
 
 
-#include "stio-prv.h"
 #include "stio-udp.h"
+#include "stio-prv.h"
 
 #include <sys/socket.h>
 #include <netinet/in.h>
@@ -43,7 +43,7 @@ static int udp_make (stio_dev_t* dev, void* ctx)
 
 	if (stio_getsckadrinfo(dev->stio, &arg->addr, &len, &family) <= -1) return -1;
 
-	udp->sck = stio_openasyncsck (family, SOCK_DGRAM);
+	udp->sck = stio_openasyncsck (dev->stio, family, SOCK_DGRAM);
 	if (udp->sck == STIO_SCKHND_INVALID) goto oops;
 
 	/* some socket options? */
@@ -53,14 +53,14 @@ static int udp_make (stio_dev_t* dev, void* ctx)
 		goto oops;
 	}
 
-	udp->on_sent = arg->on_sent;
-	udp->on_recv = arg->on_recv;
+	udp->on_write = arg->on_write;
+	udp->on_read = arg->on_read;
 	return 0;
 
 oops:
 	if (udp->sck != STIO_SCKHND_INVALID)
 	{
-		stio_closeasyncsck (udp->sck);
+		stio_closeasyncsck (udp->stio, udp->sck);
 		udp->sck = STIO_SCKHND_INVALID;
 	}
 	return -1;
@@ -71,7 +71,7 @@ static void udp_kill (stio_dev_t* dev)
 	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
 	if (udp->sck != STIO_SCKHND_INVALID) 
 	{
-		stio_closeasyncsck (udp->sck);
+		stio_closeasyncsck (udp->stio, udp->sck);
 		udp->sck = STIO_SCKHND_INVALID;
 	}
 }
@@ -82,13 +82,13 @@ static stio_syshnd_t udp_getsyshnd (stio_dev_t* dev)
 	return (stio_syshnd_t)udp->sck;
 }
 
-static int udp_recv (stio_dev_t* dev, void* buf, stio_len_t* len)
+static int udp_read (stio_dev_t* dev, void* buf, stio_len_t* len)
 {
 	stio_dev_udp_t* udp = (stio_dev_udp_t*)dev;
 	stio_scklen_t addrlen;
 	int x;
 
-/* TODO: udp_recv need source address ... have to extend the send callback to accept the source address */
+/* TODO: udp_read need source address ... have to extend the send callback to accept the source address */
 printf ("UDP RECVFROM...\n");
 	addrlen = STIO_SIZEOF(udp->peer);
 	x = recvfrom (udp->sck, buf, *len, 0, (struct sockaddr*)&udp->peer, &addrlen);
@@ -104,13 +104,13 @@ printf ("UDP RECVFROM...\n");
 	return 1;
 }
 
-static int udp_send (stio_dev_t* dev, const void* data, stio_len_t* len)
+static int udp_write (stio_dev_t* dev, const void* data, stio_len_t* len)
 {
 	stio_dev_udp_t* udp = (stio_dev_udp_t*)udp;
 	ssize_t x;
 
 #if 0
-/* TODO: udp_send need target address ... have to extend the send callback to accept the target address */
+/* TODO: udp_write need target address ... have to extend the send callback to accept the target address */
 	x = sendto (udp->sck, data, *len, skad, stio_getskadlen(skad));
 	if (x <= -1) 
 	{
@@ -137,17 +137,15 @@ static int udp_ioctl (stio_dev_t* dev, int cmd, void* arg)
 
 /* ------------------------------------------------------------------------ */
 
-// -----------------------------------------------------------------
-
 static stio_dev_mth_t udp_mth = 
 {
 	udp_make,
 	udp_kill,
 	udp_getsyshnd,
 
+	udp_read,
+	udp_write,
 	udp_ioctl,     /* ioctl */
-	udp_recv,
-	udp_send
 };
 
 static int udp_ready (stio_dev_t* dev, int events)
@@ -162,14 +160,14 @@ static int udp_ready (stio_dev_t* dev, int events)
 	return 0;
 }
 
-static int udp_on_recv (stio_dev_t* dev, const void* data, stio_len_t len)
+static int udp_on_read (stio_dev_t* dev, const void* data, stio_len_t len)
 {
 printf ("dATA received %d bytes\n", (int)len);
 	return 0;
 
 }
 
-static int udp_on_sent (stio_dev_t* dev, void* msgid)
+static int udp_on_write (stio_dev_t* dev, void* msgid)
 {
 	return 0;
 
@@ -178,8 +176,8 @@ static int udp_on_sent (stio_dev_t* dev, void* msgid)
 static stio_dev_evcb_t udp_evcb =
 {
 	udp_ready,
-	udp_on_recv,
-	udp_on_sent
+	udp_on_read,
+	udp_on_write
 };
 
 
diff --git a/stio/lib/stio-udp.h b/stio/lib/stio-udp.h
index 29fa00f..83b2a2e 100644
--- a/stio/lib/stio-udp.h
+++ b/stio/lib/stio-udp.h
@@ -29,19 +29,20 @@
 #define _STIO_UDP_H_
 
 #include <stio.h>
+#include <stio-sck.h>
 
 typedef struct stio_dev_udp_t stio_dev_udp_t;
 
-typedef int (*stio_dev_udp_on_recv_t) (stio_dev_udp_t* dev, const void* data, stio_len_t len);
-typedef int (*stio_dev_udp_on_sent_t) (stio_dev_udp_t* dev, void* sendctx);
+typedef int (*stio_dev_udp_on_read_t) (stio_dev_udp_t* dev, const void* data, stio_len_t len);
+typedef int (*stio_dev_udp_on_write_t) (stio_dev_udp_t* dev, void* wrctx);
 
 typedef struct stio_dev_udp_make_t stio_dev_udp_make_t;
 struct stio_dev_udp_make_t
 {
 	/* TODO: options: REUSEADDR for binding?? */
 	stio_sckadr_t addr; /* binding address. */
-	stio_dev_udp_on_sent_t on_sent;
-	stio_dev_udp_on_recv_t on_recv;
+	stio_dev_udp_on_write_t on_write;
+	stio_dev_udp_on_read_t on_read;
 };
 
 struct stio_dev_udp_t
@@ -50,8 +51,8 @@ struct stio_dev_udp_t
 	stio_sckhnd_t sck;
 	stio_sckadr_t peer;
 
-	stio_dev_udp_on_sent_t on_sent;
-	stio_dev_udp_on_recv_t on_recv;
+	stio_dev_udp_on_write_t on_write;
+	stio_dev_udp_on_read_t on_read;
 };
 
 #ifdef __cplusplus
diff --git a/stio/lib/stio.c b/stio/lib/stio.c
index 561a284..999c3e5 100644
--- a/stio/lib/stio.c
+++ b/stio/lib/stio.c
@@ -348,7 +348,7 @@ int stio_exec (stio_t* stio)
 				while (1)
 				{
 					len = STIO_COUNTOF(stio->bigbuf);
-					x = dev->dev_mth->recv (dev, stio->bigbuf, &len);
+					x = dev->dev_mth->read (dev, stio->bigbuf, &len);
 
 					if (x <= -1)
 					{
@@ -390,11 +390,11 @@ int stio_exec (stio_t* stio)
 						}
 						else
 						{
-				/* TODO: for a stream device, merge received data if bigbuf isn't full and fire the on_recv callback
+				/* TODO: for a stream device, merge received data if bigbuf isn't full and fire the on_read callback
 				 *        when x == 0 or <= -1. you can  */
 
 							/* data available */
-							if (dev->dev_evcb->on_recv (dev, stio->bigbuf, len) <= -1)
+							if (dev->dev_evcb->on_read (dev, stio->bigbuf, len) <= -1)
 							{
 								stio_ruindev (stio, dev);
 								dev = STIO_NULL;
@@ -421,7 +421,7 @@ int stio_exec (stio_t* stio)
 
 				send_leftover:
 					ulen = urem;
-					x = dev->dev_mth->send (dev, uptr, &ulen);
+					x = dev->dev_mth->write (dev, uptr, &ulen);
 					if (x <= -1)
 					{
 						/* TODO: error handling? call callback? or what? */
@@ -446,7 +446,7 @@ int stio_exec (stio_t* stio)
 							int y;
 
 							STIO_WQ_UNLINK (q); /* STIO_WQ_DEQ(&dev->wq); */
-							y = dev->dev_evcb->on_sent (dev, q->ctx);
+							y = dev->dev_evcb->on_write (dev, q->ctx);
 							STIO_MMGR_FREE (dev->stio->mmgr, q);
 
 							if (y <= -1)
@@ -589,7 +589,7 @@ int stio_dev_watch (stio_dev_t* dev, stio_dev_watch_cmd_t cmd, int events)
 	return 0;
 }
 
-int stio_dev_send (stio_dev_t* dev, const void* data, stio_len_t len, void* sendctx)
+int stio_dev_write (stio_dev_t* dev, const void* data, stio_len_t len, void* wrctx)
 {
 	const stio_uint8_t* uptr;
 	stio_len_t urem, ulen;
@@ -611,7 +611,7 @@ int stio_dev_send (stio_dev_t* dev, const void* data, stio_len_t len, void* send
 	while (urem > 0)
 	{
 		ulen = urem;
-		x = dev->dev_mth->send (dev, data, &ulen);
+		x = dev->dev_mth->write (dev, data, &ulen);
 		if (x <= -1) return -1;
 		else if (x == 0) goto enqueue_data; /* enqueue remaining data */
 		else 
@@ -621,7 +621,7 @@ int stio_dev_send (stio_dev_t* dev, const void* data, stio_len_t len, void* send
 		}
 	}
 
-	dev->dev_evcb->on_sent (dev, sendctx);
+	dev->dev_evcb->on_write (dev, wrctx);
 	return 0;
 
 enqueue_data:
@@ -633,7 +633,7 @@ enqueue_data:
 		return -1;
 	}
 
-	q->ctx = sendctx;
+	q->ctx = wrctx;
 	q->ptr = (stio_uint8_t*)(q + 1);
 	q->len = urem;
 	STIO_MEMCPY (q->ptr, uptr, urem);
@@ -652,6 +652,25 @@ enqueue_data:
 	return 0;
 }
 
+int stio_makesyshndasync (stio_t* stio, stio_syshnd_t hnd)
+{
+#if defined(F_GETFL) && defined(F_SETFL) && defined(O_NONBLOCK)
+	int flags;
+
+	if ((flags = fcntl (hnd, F_GETFL)) <= -1 ||
+	    (flags = fcntl (hnd, F_SETFL, flags | O_NONBLOCK)) <= -1)
+	{
+		stio->errnum = stio_syserrtoerrnum (errno);
+		return -1;
+	}
+
+	return 0;
+#else
+	stio->errnum = STIO_ENOSUP;
+	return -1;
+#endif
+}
+
 stio_errnum_t stio_syserrtoerrnum (int no)
 {
 	switch (no)
diff --git a/stio/lib/stio.h b/stio/lib/stio.h
index e947324..4115ded 100644
--- a/stio/lib/stio.h
+++ b/stio/lib/stio.h
@@ -40,51 +40,14 @@ struct stio_ntime_t
 	stio_int32_t   nsec; /* nanoseconds */
 };
 
-
-struct stio_sckadr_t
-{
-	int family;
-	stio_uint8_t data[128]; /* TODO: use the actual sockaddr size */
-};
-
-typedef struct stio_sckadr_t stio_sckadr_t;
-
-#if (STIO_SIZEOF_SOCKLEN_T == STIO_SIZEOF_INT)
-	#if defined(STIO_SOCKLEN_T_IS_SIGNED)
-		typedef int stio_scklen_t;
-	#else
-		typedef unsigned int stio_scklen_t;
-	#endif
-#elif (STIO_SIZEOF_SOCKLEN_T == STIO_SIZEOF_LONG)
-	#if defined(STIO_SOCKLEN_T_IS_SIGNED)
-		typedef long stio_scklen_t;
-	#else
-		typedef unsigned long stio_scklen_t;
-	#endif
-#else
-	typedef int stio_scklen_t;
-#endif
-
 #if defined(_WIN32)
-#	define STIO_IOCP_KEY 1
-	/*
-	typedef HANDLE stio_syshnd_t;
-	typedef SOCKET stio_sckhnd_t;
-#	define STIO_SCKHND_INVALID (INVALID_SOCKET)
-	*/
-
 	typedef stio_uintptr_t qse_syshnd_t;
-	typedef stio_uintptr_t qse_sckhnd_t;
-#	define STIO_SCKHND_INVALID (~(qse_sck_hnd_t)0)
-
+	#define STIO_SYSHND_INVALID (~(stio_uintptr_t)0)
 #else
 	typedef int stio_syshnd_t;
-	typedef int stio_sckhnd_t;
-#	define STIO_SCKHND_INVALID (-1)
-	
+	#define STIO_SYSHND_INVALID (-1)
 #endif
 
-typedef int stio_sckfam_t;
 
 /* ------------------------------------------------------------------------- */
 typedef struct stio_t stio_t;
@@ -130,18 +93,20 @@ struct stio_dev_mth_t
 	/* ------------------------------------------------------------------ */
 	stio_syshnd_t (*getsyshnd)    (stio_dev_t* dev); /* mandatory. called in stio_makedev() after successful make() */
 
-	/* ------------------------------------------------------------------ */
-	int           (*ioctl)        (stio_dev_t* dev, int cmd, void* arg);
 
 	/* ------------------------------------------------------------------ */
 	/* return -1 on failure, 0 if no data is availble, 1 otherwise.
 	 * when returning 1, *len must be sent to the length of data read.
 	 * if *len is set to 0, it's treated as EOF.
 	 * it must not kill the device */
-	int           (*recv)         (stio_dev_t* dev, void* data, stio_len_t* len);
+	int           (*read)         (stio_dev_t* dev, void* data, stio_len_t* len);
 
 	/* ------------------------------------------------------------------ */
-	int           (*send)         (stio_dev_t* dev, const void* data, stio_len_t* len);
+	int           (*write)        (stio_dev_t* dev, const void* data, stio_len_t* len);
+
+	/* ------------------------------------------------------------------ */
+	int           (*ioctl)        (stio_dev_t* dev, int cmd, void* arg);
+
 };
 
 struct stio_dev_evcb_t
@@ -154,11 +119,11 @@ struct stio_dev_evcb_t
 
 	/* return -1 on failure, 0 on success
 	 * it must not kill the device */
-	int           (*on_recv)      (stio_dev_t* dev, const void* data, stio_len_t len);
+	int           (*on_read)      (stio_dev_t* dev, const void* data, stio_len_t len);
 
 	/* return -1 on failure, 0 on success. 
 	 * it must not kill the device */
-	int           (*on_sent)      (stio_dev_t* dev, void* sendctx);
+	int           (*on_write)      (stio_dev_t* dev, void* wrctx);
 };
 
 struct stio_wq_t
@@ -340,11 +305,11 @@ STIO_EXPORT int stio_dev_watch (
 	int                  events
 );
 
-STIO_EXPORT int stio_dev_send (
+STIO_EXPORT int stio_dev_write (
 	stio_dev_t*   dev,
 	const void*   data,
 	stio_len_t    len,
-	void*         sendctx
+	void*         wrctx
 );
 
 #ifdef __cplusplus