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更新时间：2022-09-15 12:11:24
继续分析
下面这一段，当 initdb --version 或者 initdb --help 才有意义。
if (argc > 1) { if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0) { usage(progname); exit(0); } if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0) { puts("initdb (PostgreSQL) " PG_VERSION); exit(0); } }
再看下一段：
实际上就是 initdb 运行时候，后面可以跟各种参数。我这里只考虑 -D那种就好了
/* process command-line options */ while ((c = getopt_long(argc, argv, "dD:E:L:nU:WA:sT:X:", long_options, &option_index)) != -1) { switch (c) { case 'A': authmethod = xstrdup(optarg); break; case 'D': pg_data = xstrdup(optarg); break; case 'E': encoding = xstrdup(optarg); break; case 'W': pwprompt = true; break; case 'U': username = xstrdup(optarg); break; case 'd': debug = true; printf(_("Running in debug mode.\n")); break; case 'n': noclean = true; printf(_("Running in noclean mode. Mistakes will not be cleaned up.\n")); break; case 'L': share_path = xstrdup(optarg); break; case 1: locale = xstrdup(optarg); break; case 2: lc_collate = xstrdup(optarg); break; case 3: lc_ctype = xstrdup(optarg); break; case 4: lc_monetary = xstrdup(optarg); break; case 5: lc_numeric = xstrdup(optarg); break; case 6: lc_time = xstrdup(optarg); break; case 7: lc_messages = xstrdup(optarg); break; case 8: locale = "C"; break; case 9: pwfilename = xstrdup(optarg); break; case 's': show_setting = true; break; case 'T': default_text_search_config = xstrdup(optarg); break; case 'X': xlog_dir = xstrdup(optarg); break; default: /* getopt_long already emitted a complaint */ fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname); exit(1); } }
也就是这段：
case 'D': pg_data = xstrdup(optarg); break;