Fix stdbuf on NetBSD

closes #11410

Author: 0323pin

src/uu/stdbuf/src/libstdbuf/src/libstdbuf.rs

@@ -35,6 +35,11 @@ pub unsafe extern "C" fn __stdbuf_get_stdin() -> *mut FILE {
         unsafe { __stdin }
     }
 
+    #[cfg(target_os = "netbsd")]
+    {
+        unsafe { libc::fdopen(0, c"r".as_ptr()) }
+    }
+
     #[cfg(target_os = "cygwin")]
     {
         // _getreent()->_std{in,out,err}
@@ -61,6 +66,7 @@ pub unsafe extern "C" fn __stdbuf_get_stdin() -> *mut FILE {
     #[cfg(not(any(
         target_os = "macos",
         target_os = "freebsd",
+        target_os = "netbsd",
         target_os = "openbsd",
         target_os = "cygwin"
     )))]
@@ -92,6 +98,11 @@ pub unsafe extern "C" fn __stdbuf_get_stdout() -> *mut FILE {
         unsafe { __stdout }
     }
 
+    #[cfg(target_os = "netbsd")]
+    {
+        unsafe { libc::fdopen(1, c"w".as_ptr()) }
+    }
+
     #[cfg(target_os = "cygwin")]
     {
         // _getreent()->_std{in,out,err}
@@ -118,6 +129,7 @@ pub unsafe extern "C" fn __stdbuf_get_stdout() -> *mut FILE {
     #[cfg(not(any(
         target_os = "macos",
         target_os = "freebsd",
+        target_os = "netbsd",
         target_os = "openbsd",
         target_os = "cygwin"
     )))]
@@ -149,6 +161,11 @@ pub unsafe extern "C" fn __stdbuf_get_stderr() -> *mut FILE {
         unsafe { __stderr }
     }
 
+    #[cfg(target_os = "netbsd")]
+    {
+        unsafe { libc::fdopen(2, c"w".as_ptr()) }
+    }
+
     #[cfg(target_os = "cygwin")]
     {
         // _getreent()->_std{in,out,err}
@@ -175,6 +192,7 @@ pub unsafe extern "C" fn __stdbuf_get_stderr() -> *mut FILE {
     #[cfg(not(any(
         target_os = "macos",
         target_os = "freebsd",
+        target_os = "netbsd",
         target_os = "openbsd",
         target_os = "cygwin"
     )))]