Change the cfmakeraw() wrapper to handle the difference in its return type on AIX.

Author: xingxue-ibm

src/backend/libc/termios/syscalls.rs

@@ -493,7 +493,20 @@ pub(crate) fn set_input_speed(termios: &mut Termios, arbitrary_speed: u32) -> io
 #[cfg(not(any(target_os = "espidf", target_os = "nto", target_os = "wasi")))]
 #[inline]
 pub(crate) fn cfmakeraw(termios: &mut Termios) {
-    unsafe { c::cfmakeraw(as_mut_ptr(termios).cast()) }
+    unsafe {
+        // On AIX, cfmakeraw() has a return type of 'int' instead of 'void'.
+        // If the argument 'termios' is NULL, it returns -1; otherwise, it returns 0.
+        // We believe it is safe to ignore the return value.
+        #[cfg(target_os = "aix")]
+        {
+            let _ = c::cfmakeraw(as_mut_ptr(termios).cast());
+        }
+
+        #[cfg(not(target_os = "aix"))]
+        {
+            c::cfmakeraw(as_mut_ptr(termios).cast());
+        }
+    }
 }
 
 pub(crate) fn isatty(fd: BorrowedFd<'_>) -> bool {