diff --git a/src/output/pe_output_error.c b/src/output/pe_output_error.c
index 39d7fd6..af23238 100644
--- a/src/output/pe_output_error.c
+++ b/src/output/pe_output_error.c
@@ -187,7 +187,7 @@ int pe_output_error_record(
 	else if (dctx->cctx->drvflags & PERK_DRIVER_ANNOTATE_ALWAYS)
 		return pe_output_error_record_annotated(dctx,erri);
 
-	else if (isatty(STDERR_FILENO))
+	else if (isatty(pe_driver_fderr(dctx)))
 		return pe_output_error_record_annotated(dctx,erri);
 
 	else
@@ -224,7 +224,7 @@ int pe_output_error_vector(const struct pe_driver_ctx * dctx)
 	else if (dctx->cctx->drvflags & PERK_DRIVER_ANNOTATE_ALWAYS)
 		return pe_output_error_vector_annotated(dctx);
 
-	else if (isatty(STDERR_FILENO))
+	else if (isatty(pe_driver_fderr(dctx)))
 		return pe_output_error_vector_annotated(dctx);
 
 	else