[libc] Update libc.

1. Add POSIX termios implementation;
2. Add POSIX signals implementation;
3. Add stdio for each libc.

26 files changed, 711 insertions, 337 deletions

diff --git a/components/libc/compilers/armlibc/libc.c b/components/libc/compilers/armlibc/libc.c
new file mode 100644
index 0000000000..d3a4ad06d0
--- /dev/null
+++ b/components/libc/compilers/armlibc/libc.c
@@ -0,0 +1,59 @@
+/*
+ * File     : libc.c
+ * Brief    : armcc libc initialization
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <rtthread.h>
+
+#include "libc.h"
+
+#ifdef RT_USING_PTHREADS
+#include <pthread.h>
+#endif
+
+int libc_system_init(void)
+{
+#if defined(RT_USING_DFS) & defined(RT_USING_DFS_DEVFS)
+    rt_device_t dev_console;
+
+    dev_console = rt_console_get_device();
+    if (dev_console)
+    {
+    #if defined(RT_USING_POSIX_STDIN)
+        libc_stdio_set_console(dev_console->parent.name, O_RDWR);
+    #else
+        libc_stdio_set_console(dev_console->parent.name, O_WRONLY);
+    #endif
+    }
+#endif
+
+#if defined RT_USING_PTHREADS && !defined RT_USING_COMPONENTS_INIT
+    pthread_system_init();
+#endif
+
+    return 0;
+}
+INIT_COMPONENT_EXPORT(libc_system_init);
diff --git a/components/libc/compilers/armlibc/libc.h b/components/libc/compilers/armlibc/libc.h
new file mode 100644
index 0000000000..5e9f68218d
--- /dev/null
+++ b/components/libc/compilers/armlibc/libc.h
@@ -0,0 +1,37 @@
+/*
+ * File     : libc.h
+ * Brief    : armcc libc header file
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+#ifndef __RTT_LIBC_H__
+#define __RTT_LIBC_H__
+
+#include <stddef.h>
+
+int libc_system_init(void);
+
+int libc_stdio_set_console(const char* device_name, int mode);
+int libc_stdio_read (void *buffer, size_t size);
+int libc_stdio_write(void *buffer, size_t size);
+
+#endif
diff --git a/components/libc/compilers/armlibc/mem_std.c b/components/libc/compilers/armlibc/mem_std.c
index 56aa525df2..5da5bb6c6c 100644
--- a/components/libc/compilers/armlibc/mem_std.c
+++ b/components/libc/compilers/armlibc/mem_std.c
@@ -32,7 +32,7 @@ RTM_EXPORT(realloc);
 
 void *calloc(rt_size_t nelem, rt_size_t elsize)
 {
-	return rt_calloc(nelem, elsize);
+    return rt_calloc(nelem, elsize);
 }
 RTM_EXPORT(calloc);
 
diff --git a/components/libc/compilers/armlibc/stdio.c b/components/libc/compilers/armlibc/stdio.c
new file mode 100644
index 0000000000..8c9c99b3ad
--- /dev/null
+++ b/components/libc/compilers/armlibc/stdio.c
@@ -0,0 +1,70 @@
+/*
+ * File     : stdio.c
+ * Brief    : stdio/console
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      implement stdio for armcc.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <rtthread.h>
+#include "libc.h"
+
+#if defined(RT_USING_DFS) && defined(RT_USING_DFS_DEVFS)
+#include <dfs_posix.h>
+
+#define STDIO_DEVICE_NAME_MAX   32
+
+static int std_fd = -1;
+int libc_stdio_set_console(const char* device_name, int mode)
+{
+    int fd;
+    char name[STDIO_DEVICE_NAME_MAX];
+
+    snprintf(name, sizeof(name) - 1, "/dev/%s", device_name);
+    name[STDIO_DEVICE_NAME_MAX - 1] = '\0';
+
+    fd = open(name, mode, 0);
+    if (fd >= 0)
+    {
+        if (std_fd >= 0)
+        {
+            close(std_fd);
+        }
+        std_fd = fd;
+    }
+
+    return std_fd;
+}
+
+int libc_stdio_read(void *buffer, size_t size)
+{
+    return read(std_fd, buffer, size);
+}
+
+int libc_stdio_write(void *buffer, size_t size)
+{
+    return write(std_fd, buffer, size);
+}
+#endif
diff --git a/components/libc/compilers/armlibc/stubs.c b/components/libc/compilers/armlibc/stubs.c
index 395e51ecda..0de8aacb3c 100644
--- a/components/libc/compilers/armlibc/stubs.c
+++ b/components/libc/compilers/armlibc/stubs.c
@@ -2,12 +2,22 @@
  * File     : stubs.c
  * Brief    : reimplement some basic functions of arm standard c library
  *
- * This file is part of Device File System in RT-Thread RTOS
- * COPYRIGHT (C) 2004-2012, RT-Thread Development Team
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
  *
- * The license and distribution terms for this file may be
- * found in the file LICENSE in this distribution or at
- * http://www.rt-thread.org/license/LICENSE.
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Change Logs:
  * Date           Author       Notes
@@ -28,10 +38,10 @@
 
 #pragma import(__use_no_semihosting_swi)
 
-/* TODO: Standard IO device handles. */
-#define STDIN       1
-#define STDOUT      2
-#define STDERR      3
+/* Standard IO device handles. */
+#define STDIN       0
+#define STDOUT      1
+#define STDERR      2
 
 /* Standard IO device name defines. */
 const char __stdin_name[]  = "STDIN";
@@ -94,7 +104,7 @@ FILEHANDLE _sys_open(const char *name, int openmode)
     if (fd < 0)
         return -1;
     else
-        return fd + STDERR + 1;
+        return fd;
 #endif
 }
 
@@ -103,21 +113,36 @@ int _sys_close(FILEHANDLE fh)
 #ifndef RT_USING_DFS
     return 0;
 #else
-    if (fh < STDERR)
-        return 0;
+    if (fh <= STDERR) return 0;
 
-    return close(fh - STDERR - 1);
+    return close(fh);
 #endif
 }
 
-/**
- * read data
+/*
+ * Read from a file. Can return:
+ *  - zero if the read was completely successful
+ *  - the number of bytes _not_ read, if the read was partially successful
+ *  - the number of bytes not read, plus the top bit set (0x80000000), if
+ *    the read was partially successful due to end of file
+ *  - -1 if some error other than EOF occurred
  *
- * @param fh - file handle
- * @param buf - buffer to save read data
- * @param len - max length of data buffer
- * @param mode - useless, for historical reasons
- * @return The number of bytes not read.
+ * It is also legal to signal EOF by returning no data but
+ * signalling no error (i.e. the top-bit-set mechanism need never
+ * be used).
+ *
+ * So if (for example) the user is trying to read 8 bytes at a time
+ * from a file in which only 5 remain, this routine can do three
+ * equally valid things:
+ *
+ *  - it can return 0x80000003 (3 bytes not read due to EOF)
+ *  - OR it can return 3 (3 bytes not read), and then return
+ *    0x80000008 (8 bytes not read due to EOF) on the next attempt
+ *  - OR it can return 3 (3 bytes not read), and then return
+ *    8 (8 bytes not read, meaning 0 read, meaning EOF) on the next
+ *    attempt
+ *
+ * `mode' exists for historical reasons and must be ignored.
  */
 int _sys_read(FILEHANDLE fh, unsigned char *buf, unsigned len, int mode)
 {
@@ -127,8 +152,13 @@ int _sys_read(FILEHANDLE fh, unsigned char *buf, unsigned len, int mode)
 
     if (fh == STDIN)
     {
-        /* TODO */
-        return 0;
+#ifdef RT_USING_POSIX_STDIN
+        size = libc_stdio_read(buf, len);
+        return len - size;
+#else
+        /* no stdin */
+        return -1;
+#endif
     }
 
     if ((fh == STDOUT) || (fh == STDERR))
@@ -137,7 +167,7 @@ int _sys_read(FILEHANDLE fh, unsigned char *buf, unsigned len, int mode)
 #ifndef RT_USING_DFS
     return 0;
 #else
-    size = read(fh - STDERR - 1, buf, len);
+    size = read(fh, buf, len);
     if (size >= 0)
         return len - size;
     else
@@ -145,14 +175,10 @@ int _sys_read(FILEHANDLE fh, unsigned char *buf, unsigned len, int mode)
 #endif
 }
 
-/**
- * write data
- *
- * @param fh - file handle
- * @param buf - data buffer
- * @param len - buffer length
- * @param mode - useless, for historical reasons
- * @return a positive number representing the number of characters not written.
+/*
+ * Write to a file. Returns 0 on success, negative on error, and
+ * the number of characters _not_ written on partial success.
+ * `mode' exists for historical reasons and must be ignored.
  */
 int _sys_write(FILEHANDLE fh, const unsigned char *buf, unsigned len, int mode)
 {
@@ -165,22 +191,27 @@ int _sys_write(FILEHANDLE fh, const unsigned char *buf, unsigned len, int mode)
 #ifndef RT_USING_CONSOLE
         return 0;
 #else
-        rt_device_t console_device;
-
-        console_device = rt_console_get_device();
-        if (console_device != 0) rt_device_write(console_device, 0, buf, len);
+#ifdef RT_USING_POSIX_STDIN
+        size = libc_stdio_write(buf, len);
+        return len - size;
+#else
+        if (rt_console_get_device())
+        {
+            rt_device_write(rt_console_get_device(), -1, buf, len);
+            return 0;
+        }
 
-        return 0;
+        return -1;
+#endif
 #endif
     }
 
-    if (fh == STDIN)
-        return -1;
+    if (fh == STDIN) return -1;
 
 #ifndef RT_USING_DFS
     return 0;
 #else
-    size = write(fh - STDERR - 1, buf, len);
+    size = write(fh, buf, len);
     if (size >= 0)
         return len - size;
     else
@@ -188,11 +219,9 @@ int _sys_write(FILEHANDLE fh, const unsigned char *buf, unsigned len, int mode)
 #endif
 }
 
-/**
- * put he file pointer at offset pos from the beginning of the file.
- *
- * @param pos - offset
- * @return the current file position, or -1 on failed
+/*
+ * Move the file position to a given offset from the file start.
+ * Returns >=0 on success, <0 on failure.
  */
 int _sys_seek(FILEHANDLE fh, long pos)
 {
@@ -204,7 +233,7 @@ int _sys_seek(FILEHANDLE fh, long pos)
 #else
 
     /* position is relative to the start of file fh */
-    return lseek(fh - STDERR - 1, pos, 0);
+    return lseek(fh, pos, 0);
 #endif
 }
 
@@ -285,7 +314,15 @@ int fputc(int c, FILE *f)
     return 1;
 }
 
-int fgetc(FILE *f) {
-  return -1;
+int fgetc(FILE *f) 
+{
+    char ch;
+
+#ifdef RT_USING_POSIX_STDIN
+    if (libc_stdio_read(&ch, 1) == 1)
+        return ch;
+#endif
+
+    return -1;
 }
 #endif
diff --git a/components/libc/compilers/armlibc/sys/errno.h b/components/libc/compilers/armlibc/sys/errno.h
index 0aba5f5e19..8ee115ed04 100644
--- a/components/libc/compilers/armlibc/sys/errno.h
+++ b/components/libc/compilers/armlibc/sys/errno.h
@@ -1,80 +1,6 @@
 #ifndef SYS_ERRNO_H__
 #define SYS_ERRNO_H__
 
-#ifdef RT_USING_DFS
-
-#include <dfs_def.h>
-
-/* using device error codes */
-#define ENOENT          DFS_STATUS_ENOENT
-#define EIO             DFS_STATUS_EIO
-#define ENXIO           DFS_STATUS_ENXIO
-#define EBADF           DFS_STATUS_EBADF
-#define EAGAIN          DFS_STATUS_EAGAIN
-#define ENOMEM          DFS_STATUS_ENOMEM
-#define EBUSY           DFS_STATUS_EBUSY
-#define EEXIST          DFS_STATUS_EEXIST
-#define EXDEV           DFS_STATUS_EXDEV
-#define ENODEV          DFS_STATUS_ENODEV
-#define ENOTDIR         DFS_STATUS_ENOTDIR
-#define EISDIR          DFS_STATUS_EISDIR
-#define EINVAL          DFS_STATUS_EINVAL
-#define ENOSPC          DFS_STATUS_ENOSPC
-#define EROFS           DFS_STATUS_EROFS
-#define ENOSYS          DFS_STATUS_ENOSYS
-#define ENOTEMPTY       DFS_STATUS_ENOTEMPTY
-
-#else
-
-/* error codes */
-#define ENOENT          2        /* No such file or directory */
-#define EIO             5        /* I/O error */
-#define ENXIO           6        /* No such device or address */
-#define EBADF           9        /* Bad file number */
-#define EAGAIN          11       /* Try again */
-#define ENOMEM          12       /* no memory */
-#define EBUSY           16       /* Device or resource busy */
-#define EEXIST          17       /* File exists */
-#define EXDEV           18       /* Cross-device link */
-#define ENODEV          19       /* No such device */
-#define ENOTDIR         20       /* Not a directory */
-#define EISDIR          21       /* Is a directory */
-#define EINVAL          22       /* Invalid argument */
-#define ENOSPC          28       /* No space left on device */
-#define EROFS           30       /* Read-only file system */
-#define ENOSYS          38       /* Function not implemented */
-#define ENOTEMPTY       39       /* Directory not empty */
-
-#endif
-
-#define EPERM           1        /* Not super-user */
-#define ESRCH           3        /* No such process */
-#define EINTR           4        /* Interrupted system call */
-#define EACCES          13       /* Permission denied */
-#define EFAULT          14       /* Bad address */
-#define ENFILE          23       /* Too many open files in system */
-#define ERANGE          34       /* Math result not representable */
-#define EDEADLK         45       /* Deadlock condition */
-#define EBADMSG         77       /* Trying to read unreadable message */
-#define EMSGSIZE        90       /* Message too long */
-#define ENOPROTOOPT     92       /* Protocol not available */
-#define EOPNOTSUPP      95       /* Operation not supported on transport endpoint */
-#define EAFNOSUPPORT    97       /* Address family not supported by protocol */
-#define EADDRINUSE      98       /* Address already in use */
-#define EADDRNOTAVAIL   99       /* Cannot assign requested address */
-#define ENETDOWN        100      /* Network is down */
-#define ENETUNREACH     101      /* Network is unreachable */
-#define ECONNABORTED    103      /* Software caused connection abort */
-#define ECONNRESET      104      /* Connection reset by peer */
-#define ENOBUFS         105      /* No buffer space available */
-#define EISCONN         106      /* Transport endpoint is already connected */
-#define ENOTCONN        107      /* Transport endpoint is not connected */
-#define EINPROGRESS     115      /* Operation now in progress */
-#define ETIMEDOUT       116      /* Connection timed out */
-#define EHOSTUNREACH    113      /* No route to host */
-#define EALREADY        114      /* Operation already in progress */
-#define ENOTSUP         134      /* Not supported */
-#define ENSRNOTFOUND    163      /* Domain name not found */
-#define EWOULDBLOCK     EAGAIN   /* Operation would block */
+#include <rtthread.h>
 
 #endif
diff --git a/components/libc/compilers/armlibc/sys/unistd.h b/components/libc/compilers/armlibc/sys/unistd.h
index e1e0dc904c..38ba8b5072 100644
--- a/components/libc/compilers/armlibc/sys/unistd.h
+++ b/components/libc/compilers/armlibc/sys/unistd.h
@@ -6,31 +6,31 @@
 #ifdef RT_USING_DFS
 #include <dfs_posix.h>
 #else
-#define	_FREAD		0x0001	/* read enabled */
-#define	_FWRITE		0x0002	/* write enabled */
-#define	_FAPPEND	0x0008	/* append (writes guaranteed at the end) */
-#define	_FMARK		0x0010	/* internal; mark during gc() */
-#define	_FDEFER		0x0020	/* internal; defer for next gc pass */
-#define	_FASYNC		0x0040	/* signal pgrp when data ready */
-#define	_FSHLOCK	0x0080	/* BSD flock() shared lock present */
-#define	_FEXLOCK	0x0100	/* BSD flock() exclusive lock present */
-#define	_FCREAT		0x0200	/* open with file create */
-#define	_FTRUNC		0x0400	/* open with truncation */
-#define	_FEXCL		0x0800	/* error on open if file exists */
-#define	_FNBIO		0x1000	/* non blocking I/O (sys5 style) */
-#define	_FSYNC		0x2000	/* do all writes synchronously */
-#define	_FNONBLOCK	0x4000	/* non blocking I/O (POSIX style) */
-#define	_FNDELAY	_FNONBLOCK	/* non blocking I/O (4.2 style) */
-#define	_FNOCTTY	0x8000	/* don't assign a ctty on this open */
+#define _FREAD      0x0001  /* read enabled */
+#define _FWRITE     0x0002  /* write enabled */
+#define _FAPPEND    0x0008  /* append (writes guaranteed at the end) */
+#define _FMARK      0x0010  /* internal; mark during gc() */
+#define _FDEFER     0x0020  /* internal; defer for next gc pass */
+#define _FASYNC     0x0040  /* signal pgrp when data ready */
+#define _FSHLOCK    0x0080  /* BSD flock() shared lock present */
+#define _FEXLOCK    0x0100  /* BSD flock() exclusive lock present */
+#define _FCREAT     0x0200  /* open with file create */
+#define _FTRUNC     0x0400  /* open with truncation */
+#define _FEXCL      0x0800  /* error on open if file exists */
+#define _FNBIO      0x1000  /* non blocking I/O (sys5 style) */
+#define _FSYNC      0x2000  /* do all writes synchronously */
+#define _FNONBLOCK  0x4000  /* non blocking I/O (POSIX style) */
+#define _FNDELAY    _FNONBLOCK  /* non blocking I/O (4.2 style) */
+#define _FNOCTTY    0x8000  /* don't assign a ctty on this open */
 
-#define	O_RDONLY	0		/* +1 == FREAD */
-#define	O_WRONLY	1		/* +1 == FWRITE */
-#define	O_RDWR		2		/* +1 == FREAD|FWRITE */
-#define	O_APPEND	_FAPPEND
-#define	O_CREAT		_FCREAT
-#define	O_TRUNC		_FTRUNC
-#define	O_EXCL		_FEXCL
-#define O_SYNC		_FSYNC
+#define O_RDONLY    0       /* +1 == FREAD */
+#define O_WRONLY    1       /* +1 == FWRITE */
+#define O_RDWR      2       /* +1 == FREAD|FWRITE */
+#define O_APPEND    _FAPPEND
+#define O_CREAT     _FCREAT
+#define O_TRUNC     _FTRUNC
+#define O_EXCL      _FEXCL
+#define O_SYNC      _FSYNC
 #endif
 
 #endif /* _SYS_UNISTD_H */
diff --git a/components/libc/compilers/dlib/libc.c b/components/libc/compilers/dlib/libc.c
new file mode 100644
index 0000000000..ba998e9747
--- /dev/null
+++ b/components/libc/compilers/dlib/libc.c
@@ -0,0 +1,59 @@
+/*
+ * File     : libc.c
+ * Brief    : iar dlib initialization
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <rtthread.h>
+
+#include "libc.h"
+
+#ifdef RT_USING_PTHREADS
+#include <pthread.h>
+#endif
+
+int libc_system_init(void)
+{
+#if defined(RT_USING_DFS) & defined(RT_USING_DFS_DEVFS)
+    rt_device_t dev_console;
+
+    dev_console = rt_console_get_device();
+    if (dev_console)
+    {
+    #if defined(RT_USING_POSIX_STDIN)
+        libc_stdio_set_console(dev_console->parent.name, O_RDWR);
+    #else
+        libc_stdio_set_console(dev_console->parent.name, O_WRONLY);
+    #endif
+    }
+#endif
+
+#if defined RT_USING_PTHREADS && !defined RT_USING_COMPONENTS_INIT
+    pthread_system_init();
+#endif
+
+    return 0;
+}
+INIT_COMPONENT_EXPORT(libc_system_init);
diff --git a/components/libc/compilers/dlib/libc.h b/components/libc/compilers/dlib/libc.h
new file mode 100644
index 0000000000..db571d2ee1
--- /dev/null
+++ b/components/libc/compilers/dlib/libc.h
@@ -0,0 +1,38 @@
+/*
+ * File     : libc.h
+ * Brief    : iar dlib header file
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+
+#ifndef __RTT_LIBC_H__
+#define __RTT_LIBC_H__
+
+#include <stddef.h>
+
+int libc_system_init(void);
+
+int libc_stdio_set_console(const char* device_name, int mode);
+int libc_stdio_read (void *buffer, size_t size);
+int libc_stdio_write(const void *buffer, size_t size);
+
+#endif
diff --git a/components/libc/compilers/dlib/stdio.c b/components/libc/compilers/dlib/stdio.c
new file mode 100644
index 0000000000..24e421f2b3
--- /dev/null
+++ b/components/libc/compilers/dlib/stdio.c
@@ -0,0 +1,70 @@
+/*
+ * File     : stdio.c
+ * Brief    : stdio/console
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      implement stdio for IAR dlib.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <rtthread.h>
+#include "libc.h"
+
+#if defined(RT_USING_DFS) && defined(RT_USING_DFS_DEVFS)
+#include <dfs_posix.h>
+
+#define STDIO_DEVICE_NAME_MAX   32
+
+static int std_fd = -1;
+int libc_stdio_set_console(const char* device_name, int mode)
+{
+    int fd;
+    char name[STDIO_DEVICE_NAME_MAX];
+
+    snprintf(name, sizeof(name) - 1, "/dev/%s", device_name);
+    name[STDIO_DEVICE_NAME_MAX - 1] = '\0';
+
+    fd = open(name, mode, 0);
+    if (fd >= 0)
+    {
+        if (std_fd >= 0)
+        {
+            close(std_fd);
+        }
+        std_fd = fd;
+    }
+
+    return std_fd;
+}
+
+int libc_stdio_read(void *buffer, size_t size)
+{
+    return read(std_fd, buffer, size);
+}
+
+int libc_stdio_write(const void *buffer, size_t size)
+{
+    return write(std_fd, buffer, size);
+}
+#endif
diff --git a/components/libc/compilers/dlib/sys/errno.h b/components/libc/compilers/dlib/sys/errno.h
index a8e09ffd24..072892edc1 100644
--- a/components/libc/compilers/dlib/sys/errno.h
+++ b/components/libc/compilers/dlib/sys/errno.h
@@ -1,80 +1,7 @@
 #ifndef SYS_ERRNO_H__
 #define SYS_ERRNO_H__
 
-#ifdef RT_USING_DFS
+#include <rtthread.h>
 
-#include <dfs_def.h>
-
-/* using device error codes */
-#define ENOENT       DFS_STATUS_ENOENT
-#define EIO          DFS_STATUS_EIO
-#define ENXIO        DFS_STATUS_ENXIO
-#define EBADF        DFS_STATUS_EBADF
-#define EAGAIN       DFS_STATUS_EAGAIN
-#define ENOMEM       DFS_STATUS_ENOMEM
-#define EBUSY        DFS_STATUS_EBUSY
-#define EEXIST       DFS_STATUS_EEXIST
-#define EXDEV        DFS_STATUS_EXDEV
-#define ENODEV       DFS_STATUS_ENODEV
-#define ENOTDIR      DFS_STATUS_ENOTDIR
-#define EISDIR       DFS_STATUS_EISDIR
-#define EINVAL       DFS_STATUS_EINVAL
-#define ENOSPC       DFS_STATUS_ENOSPC
-#define EROFS        DFS_STATUS_EROFS
-#define ENOSYS       DFS_STATUS_ENOSYS
-#define ENOTEMPTY    DFS_STATUS_ENOTEMPTY
-
-#else
-
-/* error codes */
-#define ENOENT       2        /* No such file or directory */
-#define EIO          5        /* I/O error */
-#define ENXIO        6        /* No such device or address */
-#define EBADF        9        /* Bad file number */
-#define EAGAIN       11       /* Try again */
-#define ENOMEM       12       /* no memory */
-#define EBUSY        16       /* Device or resource busy */
-#define EEXIST       17       /* File exists */
-#define EXDEV        18       /* Cross-device link */
-#define ENODEV       19       /* No such device */
-#define ENOTDIR      20       /* Not a directory */
-#define EISDIR       21       /* Is a directory */
-#define EINVAL       22       /* Invalid argument */
-#define ENOSPC       28       /* No space left on device */
-#define EROFS        30       /* Read-only file system */
-#define ENOSYS       38       /* Function not implemented */
-#define ENOTEMPTY    39       /* Directory not empty */
-
-#endif
-
-#define EPERM                1        /* Not super-user */
-#define ESRCH                3        /* No such process */
-#define EINTR                4        /* Interrupted system call */
-#define EACCES               13       /* Permission denied */
-#define EFAULT               14       /* Bad address */
-#define ENFILE               23       /* Too many open files in system */
-#define ERANGE               34       /* Math result not representable */
-#define EDEADLK              45       /* Deadlock condition */
-#define EBADMSG              77       /* Trying to read unreadable message */
-#define EMSGSIZE             90       /* Message too long */
-#define ENOPROTOOPT          92       /* Protocol not available */
-#define EOPNOTSUPP           95       /* Operation not supported on transport endpoint */
-#define EAFNOSUPPORT         97       /* Address family not supported by protocol */
-#define EADDRINUSE           98       /* Address already in use */
-#define EADDRNOTAVAIL        99       /* Cannot assign requested address */
-#define ENETDOWN             100      /* Network is down */
-#define ENETUNREACH          101      /* Network is unreachable */
-#define ECONNABORTED         103      /* Software caused connection abort */
-#define ECONNRESET           104      /* Connection reset by peer */
-#define ENOBUFS              105      /* No buffer space available */
-#define EISCONN              106      /* Transport endpoint is already connected */
-#define ENOTCONN             107      /* Transport endpoint is not connected */
-#define EINPROGRESS          115      /* Operation now in progress */
-#define ETIMEDOUT            116      /* Connection timed out */
-#define EHOSTUNREACH         113      /* No route to host */
-#define EALREADY             114      /* Operation already in progress */
-#define ENOTSUP              134      /* Not supported */
-#define ENSRNOTFOUND         163      /* Domain name not found */
-#define EWOULDBLOCK          EAGAIN   /* Operation would block */
 
 #endif
diff --git a/components/libc/compilers/dlib/syscall_close.c b/components/libc/compilers/dlib/syscall_close.c
index c2bb0b63d6..5792bb3806 100644
--- a/components/libc/compilers/dlib/syscall_close.c
+++ b/components/libc/compilers/dlib/syscall_close.c
@@ -36,7 +36,7 @@ int __close(int handle)
         return _LLIO_ERROR;
 
 #ifdef RT_USING_DFS
-    return close(handle - _LLIO_STDERR - 1);
+    return close(handle);
 #else
     return 0;
 #endif
diff --git a/components/libc/compilers/dlib/syscall_lseek.c b/components/libc/compilers/dlib/syscall_lseek.c
index 23d509817e..950ba52f65 100644
--- a/components/libc/compilers/dlib/syscall_lseek.c
+++ b/components/libc/compilers/dlib/syscall_lseek.c
@@ -36,7 +36,7 @@ long __lseek(int handle, long offset, int whence)
         return _LLIO_ERROR;
 
 #ifdef RT_USING_DFS
-    return lseek(handle - _LLIO_STDERR - 1, offset, whence);
+    return lseek(handle, offset, whence);
 #else
     return _LLIO_ERROR;
 #endif
diff --git a/components/libc/compilers/dlib/syscall_mem.c b/components/libc/compilers/dlib/syscall_mem.c
index 10eb298b9c..05e79f50b2 100644
--- a/components/libc/compilers/dlib/syscall_mem.c
+++ b/components/libc/compilers/dlib/syscall_mem.c
@@ -35,7 +35,7 @@ void *realloc(void *rmem, rt_size_t newsize)
 
 void *calloc(rt_size_t nelem, rt_size_t elsize)
 {
-	return rt_calloc(nelem, elsize);
+    return rt_calloc(nelem, elsize);
 }
 
 void free(void *rmem)
diff --git a/components/libc/compilers/dlib/syscall_open.c b/components/libc/compilers/dlib/syscall_open.c
index 95fa43b9c6..6194707549 100644
--- a/components/libc/compilers/dlib/syscall_open.c
+++ b/components/libc/compilers/dlib/syscall_open.c
@@ -33,56 +33,56 @@
 int __open(const char *filename, int mode)
 {
 #ifndef RT_USING_DFS
-  return -1;
+  return _LLIO_ERROR;
 #else
   int handle;
   int open_mode = O_RDONLY;
-  
+
   if (mode & _LLIO_CREAT)
   {
     open_mode |= O_CREAT;
-    
+
     /* Check what we should do with it if it exists. */
     if (mode & _LLIO_APPEND)
     {
       /* Append to the existing file. */
       open_mode |= O_APPEND;
     }
-    
+
     if (mode & _LLIO_TRUNC)
     {
       /* Truncate the existsing file. */
       open_mode |= O_TRUNC;
     }
   }
-  
+
   if (mode & _LLIO_TEXT)
   {
     /* we didn't support text mode */
   }
-  
+
   switch (mode & _LLIO_RDWRMASK)
   {
   case _LLIO_RDONLY:
     break;
-    
+
   case _LLIO_WRONLY:
     open_mode |= O_WRONLY;
     break;
-    
+
   case _LLIO_RDWR:
     /* The file should be opened for both reads and writes. */
     open_mode |= O_RDWR;
     break;
-    
+
   default:
-    return -1;
+    return _LLIO_ERROR;
   }
-  
+
   handle = open(filename, open_mode, 0);
   if (handle < 0)
-    return -1;
-  
-  return handle + _LLIO_STDERR + 1;
+    return _LLIO_ERROR;
+
+  return handle;
 #endif
 }
diff --git a/components/libc/compilers/dlib/syscall_read.c b/components/libc/compilers/dlib/syscall_read.c
index aa13654189..9dcaa9df65 100644
--- a/components/libc/compilers/dlib/syscall_read.c
+++ b/components/libc/compilers/dlib/syscall_read.c
@@ -27,6 +27,7 @@
 #include <dfs_posix.h>
 #endif
 #include <yfuns.h>
+#include "libc.h"
 
 #pragma module_name = "?__read"
 size_t __read(int handle, unsigned char *buf, size_t len)
@@ -37,8 +38,11 @@ size_t __read(int handle, unsigned char *buf, size_t len)
 
     if (handle == _LLIO_STDIN)
     {
-        /* TODO */
-        return 0;
+#ifdef RT_USING_POSIX_STDIN
+        return libc_stdio_read(buf, len);
+#else
+        return _LLIO_ERROR;
+#endif
     }
 
     if ((handle == _LLIO_STDOUT) || (handle == _LLIO_STDERR))
@@ -47,7 +51,7 @@ size_t __read(int handle, unsigned char *buf, size_t len)
 #ifndef RT_USING_DFS
     return _LLIO_ERROR;
 #else
-    size = read(handle - _LLIO_STDERR - 1, buf, len);
+    size = read(handle, buf, len);
     return size;
 #endif
 }
diff --git a/components/libc/compilers/dlib/syscall_write.c b/components/libc/compilers/dlib/syscall_write.c
index a7140b9818..e2cb04000b 100644
--- a/components/libc/compilers/dlib/syscall_write.c
+++ b/components/libc/compilers/dlib/syscall_write.c
@@ -27,6 +27,7 @@
 #include <dfs_posix.h>
 #endif
 #include <yfuns.h>
+#include "libc.h"
 
 #pragma module_name = "?__write"
 
@@ -41,6 +42,10 @@ size_t __write(int handle, const unsigned char *buf, size_t len)
 #ifndef RT_USING_CONSOLE
         return _LLIO_ERROR;
 #else
+
+#ifdef RT_USING_POSIX_STDIN
+        return libc_stdio_write((void*)buf, len);
+#else
         rt_device_t console_device;
 
         console_device = rt_console_get_device();
@@ -48,14 +53,15 @@ size_t __write(int handle, const unsigned char *buf, size_t len)
 
         return len;
 #endif
+#endif
     }
 
-    if (handle == _LLIO_STDIN) return -1;
+    if (handle == _LLIO_STDIN) return _LLIO_ERROR;
 
 #ifndef RT_USING_DFS
     return _LLIO_ERROR;
 #else
-    size = write(handle - _LLIO_STDERR - 1, buf, len);
+    size = write(handle, buf, len);
     return size;
 #endif
 }
diff --git a/components/libc/compilers/dlib/unistd.h b/components/libc/compilers/dlib/unistd.h
new file mode 100644
index 0000000000..d67f8fb6f2
--- /dev/null
+++ b/components/libc/compilers/dlib/unistd.h
@@ -0,0 +1,6 @@
+#ifndef _UNISTD_H_
+#define _UNISTD_H_
+
+# include "sys/unistd.h"
+
+#endif /* _UNISTD_H_ */
diff --git a/components/libc/compilers/newlib/libc.c b/components/libc/compilers/newlib/libc.c
index 8f97e1c8b4..c06ded705e 100644
--- a/components/libc/compilers/newlib/libc.c
+++ b/components/libc/compilers/newlib/libc.c
@@ -1,52 +1,60 @@
+/*
+ * File     : libc.c
+ * Brief    : gcc libc header file
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
 #include <rtthread.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <fcntl.h>
 #include <sys/time.h>
+
 #include "libc.h"
 
 #ifdef RT_USING_PTHREADS
 #include <pthread.h>
 #endif
 
-#ifdef RT_USING_DFS
-#include <dfs_posix.h>
-
-#ifdef RT_USING_DFS_DEVFS
-#include <devfs.h>
-#endif
-
-#endif
-
 int libc_system_init(void)
 {
 #ifdef RT_USING_DFS
-    int fd;
-    struct rt_device *console_dev;
-
-#ifndef RT_USING_DFS_DEVFS
-#error Please enable devfs by defining RT_USING_DFS_DEVFS in rtconfig.h
-#endif
+    rt_device_t dev_console;
 
-    console_dev = rt_console_get_device();
-    if (console_dev)
+    dev_console = rt_console_get_device();
+    if (dev_console)
     {
-        /* initialize console device */
-        rt_console_init(console_dev->parent.name);
-
-        /* open console as stdin/stdout/stderr */
-        fd = open("/dev/console", O_RDONLY, 0); /* for stdin */
-        fd = open("/dev/console", O_WRONLY, 0); /* for stdout */
-        fd = open("/dev/console", O_WRONLY, 0); /* for stderr */
-
-        /* skip warning */
-        fd = fd;
+    #if defined(RT_USING_DFS_DEVFS) && defined(RT_USING_POSIX_STDIN)
+        libc_stdio_set_console(dev_console->parent.name, O_RDWR);
+    #else
+        libc_stdio_set_console(dev_console->parent.name, O_WRONLY);
+    #endif
     }
 #endif
 
     /* set PATH and HOME */
     putenv("PATH=/bin");
     putenv("HOME=/home");
+
 #if defined RT_USING_PTHREADS && !defined RT_USING_COMPONENTS_INIT
     pthread_system_init();
 #endif
diff --git a/components/libc/compilers/newlib/libc.h b/components/libc/compilers/newlib/libc.h
index a4f342df33..7cab52a11f 100644
--- a/components/libc/compilers/newlib/libc.h
+++ b/components/libc/compilers/newlib/libc.h
@@ -1,3 +1,28 @@
+/*
+ * File     : libc.h
+ * Brief    : gcc libc header file
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
 #ifndef __RTT_LIBC_H__
 #define __RTT_LIBC_H__
 
@@ -12,6 +37,7 @@
 #define NANOSECOND_PER_TICK     (NANOSECOND_PER_SECOND  / RT_TICK_PER_SECOND)
 
 int libc_system_init(void);
+int libc_stdio_set_console(const char* device_name, int mode);
 
 /* some time related function */
 int libc_set_time(const struct timespec *time);
diff --git a/components/libc/compilers/newlib/libc_sym.c b/components/libc/compilers/newlib/libc_sym.c
deleted file mode 100644
index 48e488f5d8..0000000000
--- a/components/libc/compilers/newlib/libc_sym.c
+++ /dev/null
@@ -1,47 +0,0 @@
-#include <rtthread.h>
-#include <rtm.h>
-
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-RTM_EXPORT(strcpy);
-RTM_EXPORT(strncpy);
-RTM_EXPORT(strlen);
-RTM_EXPORT(strcat);
-RTM_EXPORT(strstr);
-RTM_EXPORT(strchr);
-RTM_EXPORT(strcmp);
-RTM_EXPORT(strtol);
-RTM_EXPORT(strtoul);
-RTM_EXPORT(strncmp);
-
-RTM_EXPORT(memcpy);
-RTM_EXPORT(memcmp);
-RTM_EXPORT(memmove);
-RTM_EXPORT(memset);
-RTM_EXPORT(memchr);
-
-RTM_EXPORT(putchar);
-RTM_EXPORT(puts);
-RTM_EXPORT(printf);
-RTM_EXPORT(sprintf);
-RTM_EXPORT(snprintf);
-
-RTM_EXPORT(fwrite);
-
-#include <time.h>
-RTM_EXPORT(localtime);
-RTM_EXPORT(time);
-
-#include <setjmp.h>
-RTM_EXPORT(longjmp);
-RTM_EXPORT(setjmp);
-
-RTM_EXPORT(exit);
-RTM_EXPORT(abort);
-
-RTM_EXPORT(rand);
-
-#include <assert.h>
-RTM_EXPORT(__assert_func);
diff --git a/components/libc/compilers/newlib/libc_syms.c b/components/libc/compilers/newlib/libc_syms.c
new file mode 100644
index 0000000000..ed8686e5dd
--- /dev/null
+++ b/components/libc/compilers/newlib/libc_syms.c
@@ -0,0 +1,72 @@
+/*
+ * File     : libc_syms.c
+ * Brief    : exported symbols for libc.
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+#include <rtthread.h>
+#include <rtm.h>
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+RTM_EXPORT(strcpy);
+RTM_EXPORT(strncpy);
+RTM_EXPORT(strlen);
+RTM_EXPORT(strcat);
+RTM_EXPORT(strstr);
+RTM_EXPORT(strchr);
+RTM_EXPORT(strcmp);
+RTM_EXPORT(strtol);
+RTM_EXPORT(strtoul);
+RTM_EXPORT(strncmp);
+
+RTM_EXPORT(memcpy);
+RTM_EXPORT(memcmp);
+RTM_EXPORT(memmove);
+RTM_EXPORT(memset);
+RTM_EXPORT(memchr);
+
+RTM_EXPORT(putchar);
+RTM_EXPORT(puts);
+RTM_EXPORT(printf);
+RTM_EXPORT(sprintf);
+RTM_EXPORT(snprintf);
+
+RTM_EXPORT(fwrite);
+
+#include <time.h>
+RTM_EXPORT(localtime);
+RTM_EXPORT(time);
+
+#include <setjmp.h>
+RTM_EXPORT(longjmp);
+RTM_EXPORT(setjmp);
+
+RTM_EXPORT(exit);
+RTM_EXPORT(abort);
+
+RTM_EXPORT(rand);
+
+#include <assert.h>
+RTM_EXPORT(__assert_func);
diff --git a/components/libc/compilers/newlib/stdio.c b/components/libc/compilers/newlib/stdio.c
new file mode 100644
index 0000000000..276e68050c
--- /dev/null
+++ b/components/libc/compilers/newlib/stdio.c
@@ -0,0 +1,85 @@
+/*
+ * File     : stdio.c
+ * Brief    : stdio for newlib
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2006 - 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017/10/15     bernard      the first version
+ */
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <rtthread.h>
+#include "libc.h"
+
+#define STDIO_DEVICE_NAME_MAX   32
+
+static FILE* std_console = NULL;
+
+int libc_stdio_set_console(const char* device_name, int mode)
+{
+    FILE *fp;
+    char name[STDIO_DEVICE_NAME_MAX];
+    char *file_mode;
+
+    snprintf(name, sizeof(name) - 1, "/dev/%s", device_name);
+    name[STDIO_DEVICE_NAME_MAX - 1] = '\0';
+
+    if (mode == O_RDWR) file_mode = "r+";
+    else if (mode == O_WRONLY) file_mode = "wb";
+    else if (mode == O_RDONLY) file_mode = "rb";
+
+    fp = fopen(name, file_mode);
+    if (fp)
+    {
+        setvbuf(fp, NULL, _IONBF, 0);
+
+        if (std_console)
+        {
+            fclose(std_console);
+            std_console = NULL;
+        }
+        std_console = fp;
+
+        if (mode == O_RDWR)
+        {
+            _GLOBAL_REENT->_stdin  = std_console;
+        }
+        else 
+        {
+            _GLOBAL_REENT->_stdin  = NULL;
+        }
+
+        if (mode == O_RDONLY)
+        {
+            _GLOBAL_REENT->_stdout = NULL;
+            _GLOBAL_REENT->_stderr = NULL;
+        }
+        else
+        {
+            _GLOBAL_REENT->_stdout = std_console;
+            _GLOBAL_REENT->_stderr = std_console;
+        }
+
+        _GLOBAL_REENT->__sdidinit = 1;
+    }
+
+    return fileno(std_console);
+}
diff --git a/components/libc/compilers/newlib/sys/fcntl.h b/components/libc/compilers/newlib/sys/fcntl.h
index a53ca808b2..499c67260e 100644
--- a/components/libc/compilers/newlib/sys/fcntl.h
+++ b/components/libc/compilers/newlib/sys/fcntl.h
@@ -13,6 +13,4 @@
 #define O_DIRECTORY     0x0200000
 #define O_BINARY        0x0008000
 
-#include <unistd.h>
-
 #endif
diff --git a/components/libc/compilers/newlib/sys/termios.h b/components/libc/compilers/newlib/sys/termios.h
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/components/libc/compilers/newlib/sys/termios.h
diff --git a/components/libc/compilers/newlib/syscalls.c b/components/libc/compilers/newlib/syscalls.c
index ff09a4fe80..52d2361a04 100644
--- a/components/libc/compilers/newlib/syscalls.c
+++ b/components/libc/compilers/newlib/syscalls.c
@@ -205,30 +205,23 @@ _wait_r(struct _reent *ptr, int *status)
 _ssize_t
 _write_r(struct _reent *ptr, int fd, const void *buf, size_t nbytes)
 {
-	if (fd < 3)
+#ifndef RT_USING_DFS
+	if (fd == 0)
 	{
-#ifdef RT_USING_CONSOLE
-		rt_device_t console_device;
-		extern rt_device_t rt_console_get_device(void);
+		rt_device_t console;
 
-		console_device = rt_console_get_device();
-		if (console_device != 0) rt_device_write(console_device, 0, buf, nbytes);
-		return nbytes;
-#else
-        return 0;
-#endif
+		console = rt_console_get_device();
+		if (console) return rt_device_write(console, -1, buf, nbytes);
 	}
-	else
-	{
-#ifdef RT_USING_DFS
-	    _ssize_t rc;
 
-	    rc = write(fd, buf, nbytes);
-	    return rc;
+    return 0;
+
 #else
-        return 0;
+	_ssize_t rc;
+
+	rc = write(fd, buf, nbytes);
+	return rc;
 #endif
-	}
 }
 #endif