From 0443a946d3448f8dd0a55943741f34d20ac73ecc Mon Sep 17 00:00:00 2001
From: mattjala <124107509+mattjala@users.noreply.github.com>
Date: Wed, 19 Jun 2024 07:48:11 -0500
Subject: [PATCH] Clarify documentation for H5CX_get_data_transform (#4580)

* Correct comment for H5CX_get_data_transform

* Document why data transform ctx field doesnt use macro
---
 src/H5CX.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/H5CX.c b/src/H5CX.c
index d3d1ab3bed3..2b25288f41c 100644
--- a/src/H5CX.c
+++ b/src/H5CX.c
@@ -2351,7 +2351,7 @@ H5CX_get_filter_cb(H5Z_cb_t *filter_cb)
 /*-------------------------------------------------------------------------
  * Function:    H5CX_get_data_transform
  *
- * Purpose:     Retrieves the I/O filter callback function for the current API call context.
+ * Purpose:     Retrieves the data transformation expression for the current API call context.
  *
  * Return:      Non-negative on success / Negative on failure
  *
@@ -2371,6 +2371,9 @@ H5CX_get_data_transform(H5Z_data_xform_t **data_transform)
     assert(head && *head);
     assert(H5P_DEFAULT != (*head)->ctx.dxpl_id);
 
+    /* This getter does not use H5CX_RETRIEVE_PROP_VALID in order to use H5P_peek instead of H5P_get.
+       This prevents invocation of the data transform property's library-defined copy callback */
+
     /* Check if the value has been retrieved already */
     if (!(*head)->ctx.data_transform_valid) {
         /* Check for default DXPL */