* Make posix_spawn_file_actions_t an iterator

* Fix bug that caused the spawned process to not start

* Make the spawned process inherit the parent's file descriptos

src/header/spawn/file_actions.rs

@@ -33,7 +33,7 @@ pub enum Operation {
 }
 
 pub struct OperationNode {
-    operation: Operation,
+    pub operation: Operation,
     next: *const OperationNode,
 }
 
@@ -44,6 +44,32 @@ pub struct posix_spawn_file_actions_t {
     tail: *mut OperationNode,
 }
 
+pub struct FileActionsIter<'a> {
+    curr: Option<&'a OperationNode>,
+}
+
+impl<'a> Iterator for FileActionsIter<'a> {
+    type Item = &'a OperationNode;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let curr = self.curr?;
+        self.curr = unsafe { curr.next.as_ref() };
+        Some(curr)
+    }
+}
+
+impl<'a> IntoIterator for &'a posix_spawn_file_actions_t {
+    type Item = &'a OperationNode;
+
+    type IntoIter = FileActionsIter<'a>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        FileActionsIter {
+            curr: unsafe { self.head.as_ref() },
+        }
+    }
+}
+
 fn copy_op(file_actions: &mut posix_spawn_file_actions_t, op: Operation) -> Result<()> {
     let new = unsafe { malloc(size_of::<OperationNode>()) };
     let new_ref = unsafe {

src/header/spawn/mod.rs

@@ -79,8 +79,10 @@ fn spawn(
             if let Some(pid) = pid {
                 *pid = v;
             }
-        })
+        })?;
     }
+
+    Ok(())
 }
 
 #[unsafe(no_mangle)]