diff --git a/redox-rt/src/sys.rs b/redox-rt/src/sys.rs
index 672d3d086f..27c9be31c6 100644
--- a/redox-rt/src/sys.rs
+++ b/redox-rt/src/sys.rs
@@ -4,25 +4,6 @@ use core::{
     sync::atomic::{AtomicU32, Ordering},
 };
 
-pub(crate) fn format_errno(errno: usize) -> [u8; 6] {
-    let mut buf = [0u8; 6];
-    let mut n = errno;
-    let mut idx = 5;
-    if n == 0 {
-        buf[5] = b'0';
-        return buf;
-    }
-    while n > 0 && idx > 0 {
-        buf[idx] = b'0' + (n % 10) as u8;
-        n /= 10;
-        idx -= 1;
-    }
-    let start = idx + 1;
-    let mut result = [0u8; 6];
-    result[..6 - start].copy_from_slice(&buf[start..]);
-    result
-}
-
 use ioslice::IoSlice;
 use syscall::{
     Call, CallFlags, EINVAL, ERESTART, StdFsCallKind, TimeSpec,
@@ -611,32 +592,7 @@ pub fn open<T: AsRef<str>>(path: T, flags: usize) -> Result<usize> {
 
     let ns_fd = crate::current_namespace_fd()?;
     let fcntl_flags = flags & syscall::O_FCNTL_MASK;
-    let posix_fd = openat_into_posix(ns_fd, path.as_ref(), flags, fcntl_flags);
-    if let Err(ref e) = posix_fd {
-        let p = path.as_ref();
-        let mut buf = [0u8; 256];
-        let prefix = b"RB_OPEN_DIAG err=";
-        let mut len = 0;
-        buf[..prefix.len()].copy_from_slice(prefix);
-        len += prefix.len();
-        let errno_bytes = format_errno(e.errno as usize);
-        buf[len..len + errno_bytes.len()].copy_from_slice(&errno_bytes);
-        len += errno_bytes.len();
-        buf[len] = b' ';
-        len += 1;
-        let pfx2 = b"path=";
-        buf[len..len + pfx2.len()].copy_from_slice(pfx2);
-        len += pfx2.len();
-        let copy = (p.len()).min(buf.len() - len - 1);
-        buf[len..len + copy].copy_from_slice(&p.as_bytes()[..copy]);
-        len += copy;
-        buf[len] = b'\n';
-        len += 1;
-        let _ = syscall::write(2, &buf[..len]);
-    }
-    let posix_fd = posix_fd?;
-
-    Ok(posix_fd)
+    openat_into_posix(ns_fd, path.as_ref(), flags, fcntl_flags)
 }
 pub fn openat<T: AsRef<str>>(
     fd: usize,