PostgreSQL的 initdb 源代码分析之二十一

继续分析：

    setup_schema();

展开：

实质就是创建info_schema。

cmd 是：

"/home/pgsql/project/bin/postgres" --single -F -O -c search_path=pg_catalog -c exit_on_error=true -j template1 >/dev/null

infor_schem_file是：/home/pgsql/project/share/information_schema.sql

/** load info schema and populate from features file*/
static void
setup_schema(void)
{PG_CMD_DECL;char      **line;char      **lines;fputs(_("creating information schema ... "), stdout);fflush(stdout);lines = readfile(info_schema_file);///fprintf(stderr,"\n====================info_schema_file is: %s\n", info_schema_file);/** We use -j here to avoid backslashing stuff in information_schema.sql*/snprintf(cmd, sizeof(cmd),"\"%s\" %s -j template1 >%s",backend_exec, backend_options,DEVNULL);///fprintf(stderr,"\n=====================cmd is: %s \n",cmd);PG_CMD_OPEN;for (line = lines; *line != NULL; line++){PG_CMD_PUTS(*line);free(*line);}free(lines);PG_CMD_CLOSE;snprintf(cmd, sizeof(cmd),"\"%s\" %s template1 >%s",backend_exec, backend_options,DEVNULL);PG_CMD_OPEN;PG_CMD_PRINTF1("UPDATE information_schema.sql_implementation_info ""  SET character_value = '%s' ""  WHERE implementation_info_name = 'DBMS VERSION';\n",infoversion);PG_CMD_PRINTF1("COPY information_schema.sql_features ""  (feature_id, feature_name, sub_feature_id, ""  sub_feature_name, is_supported, comments) "" FROM E'%s';\n",escape_quotes(features_file));PG_CMD_CLOSE;check_ok();
}