diff --git a/doc/ref/posix.texi b/doc/ref/posix.texi
index bc8732932..341191ac2 100644
--- a/doc/ref/posix.texi
+++ b/doc/ref/posix.texi
@@ -2562,8 +2562,11 @@ code should be prepared to handle it when it is defined.
 @var{hint_socktype} was not recognized.
 
 @item EAI_SYSTEM
-A system error occurred; the error code can be found in
-@code{errno}.
+A system error occurred.  In C, the error code can be found in
+@code{errno}; this value is not accessible from Scheme, but in
+practice it provides little information about the actual error
+cause.
+@c See <http://bugs.gnu.org/13958>.
 @end table
 
 Users are encouraged to read the
diff --git a/libguile/net_db.c b/libguile/net_db.c
index 95f0040da..d7a12c50f 100644
--- a/libguile/net_db.c
+++ b/libguile/net_db.c
@@ -595,8 +595,10 @@ SCM_DEFINE (scm_getaddrinfo, "getaddrinfo", 1, 5, 0,
 	    "@item EAI_SOCKTYPE\n"
 	    "@var{hint_socktype} was not recognized.\n\n"
 	    "@item EAI_SYSTEM\n"
-	    "A system error occurred; the error code can be found in "
-	    "@code{errno}.\n"
+	    "A system error occurred.  In C, the error code can be found in "
+	    "@code{errno}; this value is not accessible from Scheme, but in\n"
+	    "practice it provides little information about the actual error "
+	    "cause.\n\n"	  /* see <http://bugs.gnu.org/13958>. */
 	    "@end table\n"
 	    "\n"
 	    "Users are encouraged to read the "