Always use close message when available.

src/context/file.rs

@@ -70,7 +70,7 @@ pub struct FileDescriptor {
 impl FileDescription {
     /// Try closing a file, although at this point the description will be destroyed anyway, if
     /// doing so fails.
-    pub fn try_close(self, wait_for_res: bool) -> Result<()> {
+    pub fn try_close(self) -> Result<()> {
         event::unregister_file(self.scheme, self.number);
 
         let scheme = scheme::schemes()
@@ -78,18 +78,14 @@ impl FileDescription {
             .ok_or(Error::new(EBADF))?
             .clone();
 
-        if wait_for_res {
-            scheme.close(self.number)
-        } else {
-            scheme.on_close(self.number)
-        }
+        scheme.on_close(self.number)
     }
 }
 
 impl FileDescriptor {
-    pub fn close(self, wait_for_res: bool) -> Result<()> {
+    pub fn close(self) -> Result<()> {
         if let Ok(file) = Arc::try_unwrap(self.description).map(RwLock::into_inner) {
-            file.try_close(wait_for_res)?;
+            file.try_close()?;
         }
         Ok(())
     }

src/context/memory.rs

@@ -71,10 +71,7 @@ impl UnmapResult {
             .and_then(|scheme| scheme.kfunmap(number, base_offset, self.size, self.flags));
 
         if let Ok(fd) = Arc::try_unwrap(description) {
-            fd.into_inner().try_close(
-                // wait_for_result
-                false,
-            )?;
+            fd.into_inner().try_close()?;
         }
         funmap_result?;
 

src/scheme/user.rs

@@ -1102,10 +1102,7 @@ impl UserInner {
         }
 
         if let Some(to_close) = to_close {
-            let _ = to_close.try_close(
-                // wait_for_result
-                false,
-            );
+            let _ = to_close.try_close();
         }
         Ok(())
     }

src/syscall/fs.rs

@@ -177,10 +177,7 @@ pub fn close(fd: FileHandle) -> Result<()> {
         context.remove_file(fd).ok_or(Error::new(EBADF))?
     };
 
-    file.close(
-        // wait_for_result
-        true,
-    )
+    file.close()
 }
 
 fn duplicate_file(fd: FileHandle, user_buf: UserSliceRo) -> Result<FileDescriptor> {

src/syscall/process.rs

@@ -50,10 +50,7 @@ pub fn exit_this_context() -> ! {
     // Files must be closed while context is valid so that messages can be passed
     for file_opt in close_files.into_iter() {
         if let Some(file) = file_opt {
-            let _ = file.close(
-                // wait_for_result
-                false,
-            );
+            let _ = file.close();
         }
     }
     drop(addrspace_opt);