fix: Enable stdout output for CEA-708 captions on Windows

src/lib_ccx/ccx_encoders_common.c

@@ -667,8 +667,13 @@ static int init_output_ctx(struct encoder_ctx *ctx, struct encoder_cfg *cfg)
 
 			if (cfg->cc_to_stdout)
 			{
+#ifdef WIN32
+				ctx->dtvcc_writers[i].fd = -1;
+				ctx->dtvcc_writers[i].fhandle = GetStdHandle(STD_OUTPUT_HANDLE);
+#else
 				ctx->dtvcc_writers[i].fd = STDOUT_FILENO;
 				ctx->dtvcc_writers[i].fhandle = NULL;
+#endif
 				ctx->dtvcc_writers[i].charset = NULL;
 				ctx->dtvcc_writers[i].filename = NULL;
 				ctx->dtvcc_writers[i].cd = (iconv_t)-1;

src/rust/src/decoder/service_decoder.rs

@@ -1118,7 +1118,6 @@ impl dtvcc_service_decoder {
 
     /// Process the character and add it to the current window
     pub fn process_character(&mut self, sym: dtvcc_symbol) {
-        debug!("{}", self.current_window);
         let window = &mut self.windows[self.current_window as usize];
         let window_state = if is_true(window.is_defined) {
             "OK"

src/rust/src/decoder/tv_screen.rs

@@ -735,4 +735,77 @@ mod test {
         assert!(!screen.is_row_empty(0));
         assert!(screen.is_row_empty(1));
     }
+
+    #[test]
+    #[cfg(unix)]
+    fn test_writer_output_with_valid_fd() {
+        // Test that writer_output works when fd is already set (stdout mode)
+        // This tests the fix for issue #1693
+        use std::fs::File;
+        use std::os::unix::io::{FromRawFd, IntoRawFd};
+        use tempfile::tempfile;
+
+        let screen = get_zero_allocated_obj::<dtvcc_tv_screen>();
+        let mut writer_ctx = get_zero_allocated_obj::<dtvcc_writer_ctx>();
+        let transcript_settings = get_zero_allocated_obj::<ccx_encoders_transcript_format>();
+
+        // Create a temp file and use its fd (simulates stdout being pre-set)
+        let temp_file = tempfile().expect("Failed to create temp file");
+        writer_ctx.fd = temp_file.into_raw_fd();
+        writer_ctx.filename = std::ptr::null_mut(); // filename is null in stdout mode
+
+        let mut counter = 0u32;
+        let mut writer = Writer::new(
+            &mut counter,
+            0,
+            ccx_output_format::CCX_OF_SRT,
+            &mut writer_ctx,
+            0,
+            &transcript_settings,
+            0,
+        );
+
+        // This should succeed without error (fd is valid, not -1)
+        let result = screen.writer_output(&mut writer);
+        assert!(
+            result.is_ok(),
+            "writer_output should succeed when fd is valid"
+        );
+
+        // Clean up: convert fd back to File so it gets closed on drop
+        let _file = unsafe { File::from_raw_fd(writer_ctx.fd) };
+    }
+
+    #[test]
+    #[cfg(unix)]
+    fn test_writer_output_missing_filename_and_fd() {
+        // Test that writer_output returns error when both filename and fd are invalid
+        // This is the expected behavior that was causing panic before the fix
+        let screen = get_zero_allocated_obj::<dtvcc_tv_screen>();
+        let mut writer_ctx = get_zero_allocated_obj::<dtvcc_writer_ctx>();
+        let transcript_settings = get_zero_allocated_obj::<ccx_encoders_transcript_format>();
+
+        // Both filename is null and fd is -1 (invalid state)
+        writer_ctx.fd = -1;
+        writer_ctx.filename = std::ptr::null_mut();
+
+        let mut counter = 0u32;
+        let mut writer = Writer::new(
+            &mut counter,
+            0,
+            ccx_output_format::CCX_OF_SRT,
+            &mut writer_ctx,
+            0,
+            &transcript_settings,
+            0,
+        );
+
+        // This should return an error, not panic
+        let result = screen.writer_output(&mut writer);
+        assert!(
+            result.is_err(),
+            "writer_output should return error when filename and fd are invalid"
+        );
+        assert_eq!(result.unwrap_err(), "Filename missing");
+    }
 }

src/rust/src/lib.rs

@@ -192,7 +192,8 @@ extern "C" {
     pub fn ccx_gxf_init(arg: *mut ccx_demuxer) -> *mut ccx_gxf;
 }
 
-/// Initialize env logger with custom format, using stdout as target
+/// Initialize env logger with custom format, using stderr as target
+/// This ensures debug output doesn't pollute stdout when using --stdout option
 ///
 /// # Safety
 ///
@@ -204,7 +205,7 @@ pub extern "C" fn ccxr_init_logger() {
     builder()
         .format(|buf, record| writeln!(buf, "[CEA-708] {}", record.args()))
         .filter_level(LevelFilter::Debug)
-        .target(Target::Stdout)
+        .target(Target::Stderr)
         .init();
 }