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
28static const char usage[] =
29"[-?\n@(#)$Id: sync (AT&T Research) 2006-10-04 $\n]"
30USAGE_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
53int
54b_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