diff --git a/platform/src/linux/mod.rs b/platform/src/linux/mod.rs
index e810f8d483d9f893849103ae71b885f44289114e..bc429b0b7ade7f2d16c843cb7fc7dc0f6a423650 100644
--- a/platform/src/linux/mod.rs
+++ b/platform/src/linux/mod.rs
@@ -57,6 +57,12 @@ pub fn fchdir(fildes: c_int) -> c_int {
     }
 }
 
+pub fn fsync(fildes: c_int) -> c_int {
+    unsafe {
+        syscall!(FSYNC, fildes) as c_int
+    }
+}
+
 #[cfg(target_arch = "x86_64")]
 pub fn open(path: *const c_char, oflag: c_int, mode: mode_t) -> c_int {
     unsafe {
diff --git a/platform/src/redox/mod.rs b/platform/src/redox/mod.rs
index f80e5fd3dea3addc746492ea8b82abcf44d7e7c4..a2a207e0cd50ffaba70e936766525aec46bed9f5 100644
--- a/platform/src/redox/mod.rs
+++ b/platform/src/redox/mod.rs
@@ -3,20 +3,18 @@ use syscall;
 use c_str;
 use types::*;
 
-pub unsafe fn cstr_to_slice<'a>(buf: *const c_char) -> &'a [u8] {
-    slice::from_raw_parts(buf as *const u8, ::strlen(buf) as usize)
-}
-
 pub fn brk(addr: *const c_void) -> {
     syscall::brk(addr as usize)? as c_int
 
-pub fn chdir(path: *const c_char) -> c_int {
-    syscall::chdir(cstr_to_slice(path))? as c_int
-}
+ pub fn chdir(path: *const c_char) -> c_int {
+    let path = unsafe { c_str(path) };
+    syscall::chdir(path)? as c_int
+ } 
+ 
 
 pub fn chown(path: *const c_char, owner: uid_t, group: gid_t) -> c_int {
     let fd = syscall::open(cstr_to_slice(path));
-    syscall::fchown(fd, owner, group)? as c_int
+    syscall::fchown(fd as usize, owner as usize, group as usize)? as c_int
 
 pub fn close(fd: c_int) -> c_int {
     syscall::close(fd as usize);
@@ -37,12 +35,20 @@ pub fn exit(status: c_int) -> ! {
 }
 
 pub fn fchown(fd: c_int, owner: uid_t, group: gid_t) -> c_int {
-    syscall::fchown(owner, group)? as c_int
+    syscall::fchown(owner as usize, group as usize)? as c_int
 }
 
 pub fn fchdir(fd: c_int) -> c_int {
-    let path = fpath(fd as usize, &[]).unwrap();
-    syscall::chdir(path)? as c_int
+    let result = fpath(fd as usize, &[]);
+    if result.is_ok() {
+        syscall::chdir(path)? as c_int
+    } else {
+        -1
+    }
+}
+
+pub fn fsync(fd: c_int) -> c_int {
+    syscall::fsync(fd as usize)? as c_int
 }
 
 pub fn open(path: *const c_char, oflag: c_int, mode: mode_t) -> c_int {
diff --git a/src/unistd/src/lib.rs b/src/unistd/src/lib.rs
index d60f11bcee45775520522de982f0b6961d59aee2..d965c7d40feac4eb6c7a690c883a57224753b53d 100644
--- a/src/unistd/src/lib.rs
+++ b/src/unistd/src/lib.rs
@@ -156,7 +156,7 @@ pub extern "C" fn fpathconf(fildes: c_int, name: c_int) -> c_long {
 
 #[no_mangle]
 pub extern "C" fn fsync(fildes: c_int) -> c_int {
-    unimplemented!();
+    platform::fsync(fildes)
 }
 
 #[no_mangle]