diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index de272c5..36240f6 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -6951,7 +6951,7 @@ myEventProc(PGEventId evtId, void *evtInfo, void *passThrough)
The connection service file can be a per-user service file
at ~/.pg_service.conf or the location
specified by the environment variable PGSERVICEFILE,
- or it can be a system-wide file
+ or it can be a system-wide under the output of pg_config --sysconfig, frequently
at /etc/pg_service.conf or in the directory
specified by the environment variable
PGSYSCONFDIR. If service definitions with the same