pg_upgrade: use "" rather than '', for Windows

If we ever support unix sockets on Windows, we should use "" rather than
'' for zero-length strings on the command-line, so use that.

diff --git a/contrib/pg_upgrade/server.c b/contrib/pg_upgrade/server.c
index c1d459dd8220e79def97d220a4e3814a1634ad04..7e972315f8ecc1357664a8ad5f511298472bdeb3 100644 (file)
--- a/contrib/pg_upgrade/server.c
+++ b/contrib/pg_upgrade/server.c
@@ -190,7 +190,7 @@ start_postmaster(ClusterInfo *cluster, bool throw_error)
 #ifdef HAVE_UNIX_SOCKETS
    /* prevent TCP/IP connections, restrict socket access */
    strcat(socket_string,
-          " -c listen_addresses='' -c unix_socket_permissions=0700");
+          " -c listen_addresses=\"\" -c unix_socket_permissions=0700");
 
    /* Have a sockdir?  Tell the postmaster. */
    if (cluster->sockdir)