+
+#[test]
+#[cfg(any(target_os = "linux", target_os = "macos", target_os = "ios", target_os = "watchos"))]
+fn test_named_thread_truncation() {
+ use crate::thread::{self, Builder};
+
+ let long_name = crate::iter::once("test_named_thread_truncation")
+ .chain(crate::iter::repeat(" yada").take(100))
+ .collect::<String>();
+
+ let result = Builder::new().name(long_name.clone()).spawn(move || {
+ // Rust remembers the full thread name itself.
+ assert_eq!(thread::current().name(), Some(long_name.as_str()));
+
+ // But the kernel is limited -- make sure we successfully set a truncation.
+ let mut buf = vec![0u8; long_name.len() + 1];
+ unsafe {
+ libc::pthread_getname_np(libc::pthread_self(), buf.as_mut_ptr().cast(), buf.len());
+ }
+ let cstr = CStr::from_bytes_until_nul(&buf).unwrap();
+ assert!(cstr.to_bytes().len() > 0);
+ assert!(long_name.as_bytes().starts_with(cstr.to_bytes()));
+ });
+ result.unwrap().join().unwrap();
+}