From 7d17e1d36c4f0df71e9ff8d0a20a07f9c35bbb61 Mon Sep 17 00:00:00 2001
From: =?utf8?q?P=C3=A1draig=20Brady?= <P@draigBrady.com>
Date: Mon, 3 Nov 2025 12:44:07 +0000
Subject: [PATCH] date: promptly diagnose write errors with --file

* src/date.c (batch_convert): Check error state of stdout
after each date is processed.
* tests/misc/write-errors.sh: Add a test case.
---
 src/date.c                 | 3 +++
 tests/misc/write-errors.sh | 1 +
 2 files changed, 4 insertions(+)

diff --git a/src/date.c b/src/date.c
index db16f3225a..91651e794f 100644
--- a/src/date.c
+++ b/src/date.c
@@ -448,6 +448,9 @@ batch_convert (char const *input_filename,
         {
           ok &= show_date_helper (format, format_in_c_locale, when, tz);
         }
+
+      if (ferror (stdout))
+        write_error ();
     }
 
   if (fclose (in_stream) == EOF)
diff --git a/tests/misc/write-errors.sh b/tests/misc/write-errors.sh
index b33e84a3d6..612658c6a6 100755
--- a/tests/misc/write-errors.sh
+++ b/tests/misc/write-errors.sh
@@ -30,6 +30,7 @@ cat /dev/zero
 comm -z /dev/zero /dev/zero
 cut -z -c1- /dev/zero
 cut -z -f1- /dev/zero
+date --version; yes 0 | date -f-
 dd if=/dev/zero
 expand /dev/zero
 factor --version; yes 1 | factor
-- 
2.47.3