1 files changed, 7 insertions, 2 deletions

diff --git a/src/editfns.c b/src/editfns.c
index 5c9c34dc352..6ba09cceec4 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -1233,7 +1233,11 @@ return "unknown".
 If optional argument UID is an integer, return the full name
 of the user with that uid, or nil if there is no such user.
 If UID is a string, return the full name of the user with that login
-name, or nil if there is no such user.  */)
+name, or nil if there is no such user.
+
+If the full name includes commas, remove everything starting with
+the first comma, because the \\='gecos\\=' field of the \\='/etc/passwd\\=' file
+is in general a comma-separated list.  */)
   (Lisp_Object uid)
 {
   struct passwd *pw;
@@ -1263,7 +1267,8 @@ name, or nil if there is no such user.  */)
     return Qnil;
 
   p = USER_FULL_NAME;
-  /* Chop off everything after the first comma. */
+  /* Chop off everything after the first comma, since 'pw_gecos' is a
+     comma-separated list. */
   q = strchr (p, ',');
   full = make_string (p, q ? q - p : strlen (p));