Fix for F_DUPFD_CLOEXEC, add TODO for usage in upper table

redox-rt/src/proc.rs

@@ -689,6 +689,7 @@ impl FdGuard<false> {
     pub fn to_upper(self) -> Result<FdGuardUpper> {
         // Move to upper table if necessary
         let fd = if self.fd & syscall::UPPER_FDTBL_TAG == 0 {
+            //TODO: use F_DUPFD_CLOEXEC?
             let fd = syscall::fcntl(self.fd, syscall::F_DUPFD, syscall::UPPER_FDTBL_TAG)?;
             drop(self);
             fd

src/header/fcntl/mod.rs

@@ -31,7 +31,7 @@ pub const F_SETFL: c_int = 4;
 pub const F_GETLK: c_int = 5;
 pub const F_SETLK: c_int = 6;
 pub const F_SETLKW: c_int = 7;
-pub cosnt F_DUPFD_CLOEXEC: c_int = 1030;
+pub const F_DUPFD_CLOEXEC: c_int = 1030;
 
 pub const F_RDLCK: c_int = 0;
 pub const F_WRLCK: c_int = 1;