1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1992-2012 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Eclipse Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.eclipse.org/org/documents/epl-v10.html *
11 * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <gsf@research.att.com> *
18 * David Korn <dgk@research.att.com> *
19 * *
20 ***********************************************************************/
21 #pragma prototyped
22 /*
23 * David Korn
24 * Glenn Fowler
25 * AT&T Research
26 */
27
28 static const char usage[] =
29 "[-?\n@(#)$Id: sync (AT&T Research) 2006-10-04 $\n]"
30 USAGE_LICENSE
31 "[+NAME?sync - schedule file system updates]"
32 "[+DESCRIPTION?\bsync\b calls \bsync\b(2), which causes all information "
33 "in memory that updates file systems to be scheduled for writing out to "
34 "all file systems. The writing, although scheduled, is not necessarily "
35 "complete upon return from \bsync\b.]"
36 "[+?Since \bsync\b(2) has no failure indication, \bsync\b only fails for "
37 "option/operand syntax errors, or when \bsync\b(2) does not return, in "
38 "which case \bsync\b also does not return.]"
39 "[+?At minimum \bsync\b should be called before halting the system. Most "
40 "systems provide graceful shutdown procedures that include \bsync\b -- "
41 "use them if possible.]"
42 "[+EXIT STATUS?]"
43 "{"
44 "[+0?\bsync\b(2) returned.]"
45 "[+>0?Option/operand syntax error.]"
46 "}"
47 "[+SEE ALSO?\bsync\b(2), \bshutdown\b(8)]"
48 ;
49
50 #include <cmd.h>
51 #include <ls.h>
52
53 int
b_sync(int argc,char ** argv,Shbltin_t * context)54 b_sync(int argc, char** argv, Shbltin_t* context)
55 {
56 cmdinit(argc, argv, context, ERROR_CATALOG, 0);
57 for (;;)
58 {
59 switch (optget(argv, usage))
60 {
61 case ':':
62 error(2, "%s", opt_info.arg);
63 break;
64 case '?':
65 error(ERROR_usage(2), "%s", opt_info.arg);
66 break;
67 }
68 break;
69 }
70 argv += opt_info.index;
71 if (error_info.errors || *argv)
72 error(ERROR_usage(2), "%s", optusage(NiL));
73 #if _lib_sync
74 sync();
75 #else
76 error(ERROR_usage(2), "failed -- the native system does not provide a sync(2) call");
77 #endif
78 return 0;
79 }
80