diff --git a/components/libc/posix/src/SConscript b/components/libc/posix/src/SConscript
index 24c4ede4e1e303f1104f9ec047513931cc8a39e2..b4454f6a520e9265c5352b8ed7a13d16c2f026a2 100644
--- a/components/libc/posix/src/SConscript
+++ b/components/libc/posix/src/SConscript
@@ -2,7 +2,7 @@
 
 from building import *
 
-src     = ['unistd.c']
+src     = ['unistd.c', 'delay.c']
 cwd     = GetCurrentDir()
 CPPPATH = [cwd]
 
@@ -15,9 +15,6 @@ if GetDepend('RT_USING_POSIX_POLL'):
 if GetDepend('RT_USING_POSIX_SELECT'):
     src += ['select.c']
 
-if GetDepend('RT_USING_POSIX_DELAY'):
-    src += ['delay.c']
-
 group = DefineGroup('POSIX', src, depend = ['RT_USING_POSIX'], CPPPATH = CPPPATH)
 
 Return('group')
diff --git a/components/libc/posix/src/delay.c b/components/libc/posix/src/delay.c
index 3842eb0aa8ea5c20e07a12cadf2c15b70c74e55d..c8564dc54e1b08985204b03871d04102d5fa21f2 100644
--- a/components/libc/posix/src/delay.c
+++ b/components/libc/posix/src/delay.c
@@ -7,6 +7,7 @@
  * Date           Author       Notes
  * 2021-05-07     Meco Man     first Version
  */
+#include <sys/types.h>
 #include <rtthread.h>
 #include <rthw.h>
 #define DBG_TAG    "POSIX.delay"
diff --git a/components/libc/posix/src/unistd.c b/components/libc/posix/src/unistd.c
index 6527994c9345a09fea22e69dc570a8ad57f6f7a8..85235965ea5cf9360fe384d54eddd9244d7c3ccb 100644
--- a/components/libc/posix/src/unistd.c
+++ b/components/libc/posix/src/unistd.c
@@ -13,7 +13,6 @@
 #include <dfs_private.h>
 #include <sys/errno.h>
 #include <unistd.h>
-#include <delay.h>
 
 /**
  * this function is a POSIX compliant version, which will open a file and
diff --git a/components/net/Kconfig b/components/net/Kconfig
index 18a5e44db54feb2f950516902a2f6416316fcf44..4d6317bac6b826d3e94b0f922f24e9bfa45186b8 100644
--- a/components/net/Kconfig
+++ b/components/net/Kconfig
@@ -41,7 +41,6 @@ config RT_USING_SAL
         config SAL_USING_POSIX
             bool "Enable BSD socket operated by file system API"
             default n
-            select RT_USING_LIBC
             select RT_USING_POSIX
             select RT_USING_POSIX_SELECT
             help