diff --git a/src/main.rs b/src/main.rs
index 438b2fb..309a60c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -120,7 +120,15 @@ fn read_key_file(path: &Path) -> Result<SecretBytes32, FcryError> {
     warn_if_key_file_world_readable(path);
     let mut file = File::open(path)?;
     let mut buf = Zeroizing::new([0u8; 33]);
-    let n = file.read(&mut *buf)?;
+    let mut n = 0usize;
+    while n < buf.len() {
+        match file.read(&mut buf[n..]) {
+            Ok(0) => break,
+            Ok(read) => n += read,
+            Err(e) if e.kind() == std::io::ErrorKind::Interrupted => continue,
+            Err(e) => return Err(e.into()),
+        }
+    }
     if n < 32 {
         return Err(FcryError::Format(format!(
             "key file {} is too short: expected exactly 32 bytes, got {n}",
diff --git a/tests/roundtrip.rs b/tests/roundtrip.rs
index 1da119a..eccfdbd 100644
--- a/tests/roundtrip.rs
+++ b/tests/roundtrip.rs
@@ -419,6 +419,56 @@ fn non_utf8_key_file_roundtrips() {
     assert_eq!(fs::read(&rt).unwrap(), data);
 }
 
+#[cfg(unix)]
+#[test]
+fn split_fifo_key_file_read_roundtrips() {
+    use std::ffi::CString;
+    use std::fs::OpenOptions;
+    use std::os::unix::ffi::OsStrExt;
+    use std::thread;
+    use std::time::Duration;
+
+    let dir = TempDir::new().unwrap();
+    let fifo = dir.path().join("key.fifo");
+    let fifo_c = CString::new(fifo.as_os_str().as_bytes()).unwrap();
+    let rc = unsafe { libc::mkfifo(fifo_c.as_ptr(), 0o600) };
+    assert_eq!(rc, 0, "mkfifo failed: {}", std::io::Error::last_os_error());
+
+    let plain = dir.path().join("plain.bin");
+    let ct = dir.path().join("ct.bin");
+    let rt = dir.path().join("rt.bin");
+    let data = pseudo_random(33, 8192);
+    fs::write(&plain, &data).unwrap();
+
+    let fifo_writer = fifo.clone();
+    let writer = thread::spawn(move || {
+        let mut file = OpenOptions::new().write(true).open(&fifo_writer).unwrap();
+        file.write_all(&KEY[..8]).unwrap();
+        file.flush().unwrap();
+        thread::sleep(Duration::from_millis(50));
+        file.write_all(&KEY[8..]).unwrap();
+    });
+
+    let enc = fcry()
+        .arg("-i")
+        .arg(&plain)
+        .arg("-o")
+        .arg(&ct)
+        .arg("--key-file")
+        .arg(&fifo)
+        .output()
+        .unwrap();
+    writer.join().unwrap();
+    assert!(
+        enc.status.success(),
+        "split FIFO key encrypt failed: {}",
+        String::from_utf8_lossy(&enc.stderr)
+    );
+
+    decrypt_file(&ct, &rt);
+    assert_eq!(fs::read(&rt).unwrap(), data);
+}
+
 #[test]
 fn roundtrip_passphrase_argon2id() {
     let dir = TempDir::new().unwrap();