diff --git a/cfg/posix.cfg b/cfg/posix.cfg
index edf5b293a..c33a774af 100644
--- a/cfg/posix.cfg
+++ b/cfg/posix.cfg
@@ -226,6 +226,36 @@
     </arg>
     <leak-ignore/>
   </function>
+  <!-- int lchown(const char *path, uid_t owner, gid_t group); -->
+  <function name="lchown">
+    <noreturn>false</noreturn>
+    <arg nr="1">
+      <not-uninit/>
+      <not-null/>
+    </arg>
+    <arg nr="2">
+      <not-uninit/>
+    </arg>
+    <arg nr="3">
+      <not-uninit/>
+    </arg>
+    <leak-ignore/>
+  </function>
+  <!-- int fchown(int fildes, uid_t owner, gid_t group); -->
+  <function name="fchown">
+    <noreturn>false</noreturn>
+    <arg nr="1">
+      <not-uninit/>
+      <not-null/>
+    </arg>
+    <arg nr="2">
+      <not-uninit/>
+    </arg>
+    <arg nr="3">
+      <not-uninit/>
+    </arg>
+    <leak-ignore/>
+  </function>
   <!-- int utime(const char *filename, struct utimbuf *buf); -->
   <function name="utime">
     <noreturn>false</noreturn>
@@ -264,8 +294,10 @@
       <not-uninit/>
     </arg>
   </function>
+  <!-- int isatty(int fildes); -->
   <function name="isatty">
     <noreturn>false</noreturn>
+    <use-retval/>
     <arg nr="1">
       <not-uninit/>
     </arg>
@@ -807,6 +839,14 @@
     <noreturn>false</noreturn>
     <use-retval/>
   </function>
+  <!-- char *getwd(char *path_name);-->
+  <function name="getwd">
+    <noreturn>false</noreturn>
+    <arg nr="1">
+      <not-null/>
+    </arg>
+    <leak-ignore/>
+  </function>
   <memory>
     <dealloc>free</dealloc>
     <alloc init="true">strdup</alloc>