diff --git a/components/libc/Kconfig b/components/libc/Kconfig
index a2b8747ef6c0e5d4c47d197acf94802d3aeae2f1..04d59051b8a2984dbb3ac76b35bc7cccdc556205 100644
--- a/components/libc/Kconfig
+++ b/components/libc/Kconfig
@@ -43,18 +43,28 @@ config RT_USING_POSIX
     default n
 
 if RT_USING_POSIX
-    config RT_USING_POSIX_MMAP
-        bool "Enable mmap() API"
+
+    config RT_USING_POSIX_POLL
+        bool "Enable poll()"
         default n
 
-    config RT_USING_POSIX_TERMIOS
-        bool "Enable termios APIs"
+    config RT_USING_POSIX_SELECT
+        bool "Enable select()"
+        select RT_USING_POSIX_POLL
         default n
 
     config RT_USING_POSIX_GETLINE
         bool "Enable getline()/getdelim() APIs"
         default n
 
+    config RT_USING_POSIX_MMAP
+        bool "Enable mmap() API"
+        default n
+
+    config RT_USING_POSIX_TERMIOS
+        bool "Enable termios APIs"
+        default n
+
     config RT_USING_POSIX_AIO
         bool "Enable AIO"
         default n
diff --git a/components/libc/posix/src/SConscript b/components/libc/posix/src/SConscript
index 8712d671c0e606f5e1877a60cbd3185fbb0184cb..384e71261ac967064d88f3e0f7cd5ec21a2a5647 100644
--- a/components/libc/posix/src/SConscript
+++ b/components/libc/posix/src/SConscript
@@ -2,10 +2,16 @@
 
 from building import *
 
-src     = Glob('*.c')
+src     = ['libc.c','delay.c','unistd.c']
 cwd     = GetCurrentDir()
 CPPPATH = [cwd]
 
+if GetDepend('RT_USING_POSIX_POLL'):
+    src += ['poll.c']
+
+if GetDepend('RT_USING_POSIX_SELECT'):
+    src += ['select.c']
+
 group = DefineGroup('POSIX', src, depend = ['RT_USING_POSIX'], CPPPATH = CPPPATH)
 
 Return('group')
diff --git a/components/net/Kconfig b/components/net/Kconfig
index 4c49f4aa97ba3afcc90183cfd9b9185c143053c3..eaec96b931adae44dc61305725b314df03879933 100644
--- a/components/net/Kconfig
+++ b/components/net/Kconfig
@@ -42,6 +42,7 @@ config RT_USING_SAL
             bool "Enable BSD socket operated by file system API"
             default n
             select RT_LIBC_USING_FILEIO
+            select RT_USING_POSIX_SELECT
             help
                 Let BSD socket operated by file system API, such as read/write and involveed in select/poll POSIX APIs.