1 /* date - print or set the system date and time
2 Copyright (C) 1989-2007 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 David MacKenzie <djm@gnu.ai.mit.edu> */
23 #include <sys/types.h>
24 #if HAVE_LANGINFO_CODESET
25 # include <langinfo.h>
36 #include "stat-time.h"
37 #include "fprintftime.h"
39 /* The official name of this program (e.g., no `g' prefix). */
40 #define PROGRAM_NAME "date"
42 #define AUTHORS "David MacKenzie"
46 static bool show_date (const char *format, struct timespec when);
50 /* Display only the date. */
52 /* Display date, hours, minutes, and seconds. */
54 /* Similar, but display nanoseconds. */
57 /* Put these last, since they aren't valid for --rfc-3339. */
59 /* Display date and hour. */
61 /* Display date, hours, and minutes. */
65 static char const *const time_spec_string[] =
67 /* Put "hours" and "minutes" first, since they aren't valid for
70 "date", "seconds", "ns", NULL
72 static enum Time_spec const time_spec[] =
74 TIME_SPEC_HOURS, TIME_SPEC_MINUTES,
75 TIME_SPEC_DATE, TIME_SPEC_SECONDS, TIME_SPEC_NS
77 ARGMATCH_VERIFY (time_spec_string, time_spec);
79 /* A format suitable for Internet RFC 2822. */
80 static char const rfc_2822_format[] = "%a, %d %b %Y %H:%M:%S %z";
82 /* The name this program was run with, for error messages. */
85 /* For long options that have no equivalent short option, use a
86 non-character as a pseudo short option, starting with CHAR_MAX + 1. */
89 RFC_3339_OPTION = CHAR_MAX + 1
92 static char const short_options[] = "d:f:I::r:Rs:u";
94 static struct option const long_options[] =
96 {"date", required_argument, NULL, 'd'},
97 {"file", required_argument, NULL, 'f'},
98 {"iso-8601", optional_argument, NULL, 'I'}, /* Deprecated. */
99 {"reference", required_argument, NULL, 'r'},
100 {"rfc-822", no_argument, NULL, 'R'},
101 {"rfc-2822", no_argument, NULL, 'R'},
102 {"rfc-3339", required_argument, NULL, RFC_3339_OPTION},
103 {"set", required_argument, NULL, 's'},
104 {"uct", no_argument, NULL, 'u'},
105 {"utc", no_argument, NULL, 'u'},
106 {"universal", no_argument, NULL, 'u'},
107 {GETOPT_HELP_OPTION_DECL},
108 {GETOPT_VERSION_OPTION_DECL},
113 # define TZSET tzset ()
115 # define TZSET /* empty */
119 # define DATE_FMT_LANGINFO() nl_langinfo (_DATE_FMT)
121 # define DATE_FMT_LANGINFO() ""
127 if (status != EXIT_SUCCESS)
128 fprintf (stderr, _("Try `%s --help' for more information.\n"),
133 Usage: %s [OPTION]... [+FORMAT]\n\
134 or: %s [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]\n\
136 program_name, program_name);
138 Display the current time in the given FORMAT, or set the system date.\n\
140 -d, --date=STRING display time described by STRING, not `now'\n\
141 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
144 -r, --reference=FILE display the last modification time of FILE\n\
145 -R, --rfc-2822 output date and time in RFC 2822 format.\n\
146 Example: Mon, 07 Aug 2006 12:34:56 -0600\n\
149 --rfc-3339=TIMESPEC output date and time in RFC 3339 format.\n\
150 TIMESPEC=`date', `seconds', or `ns' for\n\
151 date and time to the indicated precision.\n\
152 Date and time components are separated by\n\
153 a single space: 2006-08-07 12:34:56-06:00\n\
154 -s, --set=STRING set time described by STRING\n\
155 -u, --utc, --universal print or set Coordinated Universal Time\n\
157 fputs (HELP_OPTION_DESCRIPTION, stdout);
158 fputs (VERSION_OPTION_DESCRIPTION, stdout);
161 FORMAT controls the output. The only valid option for the second form\n\
162 specifies Coordinated Universal Time. Interpreted sequences are:\n\
165 %a locale's abbreviated weekday name (e.g., Sun)\n\
168 %A locale's full weekday name (e.g., Sunday)\n\
169 %b locale's abbreviated month name (e.g., Jan)\n\
170 %B locale's full month name (e.g., January)\n\
171 %c locale's date and time (e.g., Thu Mar 3 23:05:25 2005)\n\
174 %C century; like %Y, except omit last two digits (e.g., 21)\n\
175 %d day of month (e.g, 01)\n\
176 %D date; same as %m/%d/%y\n\
177 %e day of month, space padded; same as %_d\n\
180 %F full date; same as %Y-%m-%d\n\
181 %g last two digits of year of ISO week number (see %G)\n\
182 %G year of ISO week number (see %V); normally useful only with %V\n\
188 %j day of year (001..366)\n\
194 %M minute (00..59)\n\
198 %N nanoseconds (000000000..999999999)\n\
199 %p locale's equivalent of either AM or PM; blank if not known\n\
200 %P like %p, but lower case\n\
201 %r locale's 12-hour clock time (e.g., 11:11:04 PM)\n\
202 %R 24-hour hour and minute; same as %H:%M\n\
203 %s seconds since 1970-01-01 00:00:00 UTC\n\
206 %S second (00..60)\n\
208 %T time; same as %H:%M:%S\n\
209 %u day of week (1..7); 1 is Monday\n\
212 %U week number of year, with Sunday as first day of week (00..53)\n\
213 %V ISO week number, with Monday as first day of week (01..53)\n\
214 %w day of week (0..6); 0 is Sunday\n\
215 %W week number of year, with Monday as first day of week (00..53)\n\
218 %x locale's date representation (e.g., 12/31/99)\n\
219 %X locale's time representation (e.g., 23:13:48)\n\
220 %y last two digits of year (00..99)\n\
224 %z +hhmm numeric timezone (e.g., -0400)\n\
225 %:z +hh:mm numeric timezone (e.g., -04:00)\n\
226 %::z +hh:mm:ss numeric time zone (e.g., -04:00:00)\n\
227 %:::z numeric time zone with : to necessary precision (e.g., -04, +05:30)\n\
228 %Z alphabetic time zone abbreviation (e.g., EDT)\n\
230 By default, date pads numeric fields with zeroes.\n\
233 The following optional flags may follow `%':\n\
235 - (hyphen) do not pad the field\n\
236 _ (underscore) pad with spaces\n\
237 0 (zero) pad with zeros\n\
238 ^ use upper case if possible\n\
239 # use opposite case if possible\n\
243 After any flags comes an optional field width, as a decimal number;\n\
244 then an optional modifier, which is either\n\
245 E to use the locale's alternate representations if available, or\n\
246 O to use the locale's alternate numeric symbols if available.\n\
248 printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
253 /* Parse each line in INPUT_FILENAME as with --date and display each
254 resulting time and date. If the file cannot be opened, tell why
255 then exit. Issue a diagnostic for any lines that cannot be parsed.
256 Return true if successful. */
259 batch_convert (const char *input_filename, const char *format)
265 struct timespec when;
267 if (STREQ (input_filename, "-"))
269 input_filename = _("standard input");
274 in_stream = fopen (input_filename, "r");
275 if (in_stream == NULL)
277 error (EXIT_FAILURE, errno, "%s", quote (input_filename));
286 ssize_t line_length = getline (&line, &buflen, in_stream);
289 /* FIXME: detect/handle error here. */
293 if (! get_date (&when, line, NULL))
295 if (line[line_length - 1] == '\n')
296 line[line_length - 1] = '\0';
297 error (0, 0, _("invalid date %s"), quote (line));
302 ok &= show_date (format, when);
306 if (fclose (in_stream) == EOF)
307 error (EXIT_FAILURE, errno, "%s", quote (input_filename));
315 main (int argc, char **argv)
318 const char *datestr = NULL;
319 const char *set_datestr = NULL;
320 struct timespec when;
321 bool set_date = false;
322 char const *format = NULL;
323 char *batch_file = NULL;
324 char *reference = NULL;
325 struct stat refstats;
327 int option_specified_date;
329 initialize_main (&argc, &argv);
330 program_name = argv[0];
331 setlocale (LC_ALL, "");
332 bindtextdomain (PACKAGE, LOCALEDIR);
333 textdomain (PACKAGE);
335 atexit (close_stdout);
337 while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
340 char const *new_format = NULL;
350 case RFC_3339_OPTION:
352 static char const rfc_3339_format[][32] =
355 "%Y-%m-%d %H:%M:%S%:z",
356 "%Y-%m-%d %H:%M:%S.%N%:z"
359 XARGMATCH ("--rfc-3339", optarg,
360 time_spec_string + 2, time_spec + 2);
361 new_format = rfc_3339_format[i];
366 static char const iso_8601_format[][32] =
369 "%Y-%m-%dT%H:%M:%S%z",
370 "%Y-%m-%dT%H:%M:%S,%N%z",
376 ? XARGMATCH ("--iso-8601", optarg, time_spec_string, time_spec)
378 new_format = iso_8601_format[i];
385 new_format = rfc_2822_format;
388 set_datestr = optarg;
392 /* POSIX says that `date -u' is equivalent to setting the TZ
393 environment variable, so this option should do nothing other
395 if (putenv ("TZ=UTC0") != 0)
399 case_GETOPT_HELP_CHAR;
400 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
402 usage (EXIT_FAILURE);
408 error (EXIT_FAILURE, 0, _("multiple output formats specified"));
413 option_specified_date = ((datestr ? 1 : 0)
414 + (batch_file ? 1 : 0)
415 + (reference ? 1 : 0));
417 if (option_specified_date > 1)
420 _("the options to specify dates for printing are mutually exclusive"));
421 usage (EXIT_FAILURE);
424 if (set_date && option_specified_date)
427 _("the options to print and set the time may not be used together"));
428 usage (EXIT_FAILURE);
433 if (optind + 1 < argc)
435 error (0, 0, _("extra operand %s"), quote (argv[optind + 1]));
436 usage (EXIT_FAILURE);
439 if (argv[optind][0] == '+')
442 error (EXIT_FAILURE, 0, _("multiple output formats specified"));
443 format = argv[optind++] + 1;
445 else if (set_date || option_specified_date)
448 _("the argument %s lacks a leading `+';\n"
449 "When using an option to specify date(s), any non-option\n"
450 "argument must be a format string beginning with `+'."),
451 quote (argv[optind]));
452 usage (EXIT_FAILURE);
458 format = DATE_FMT_LANGINFO ();
461 /* Do not wrap the following literal format string with _(...).
462 For example, suppose LC_ALL is unset, LC_TIME="POSIX",
463 and LANG="ko_KR". In that case, POSIX says that LC_TIME
464 determines the format and contents of date and time strings
465 written by date, which means "date" must generate output
466 using the POSIX locale; but adding _() would cause "date"
467 to use a Korean translation of the format. */
468 format = "%a %b %e %H:%M:%S %Z %Y";
472 if (batch_file != NULL)
473 ok = batch_convert (batch_file, format);
476 bool valid_date = true;
479 if (!option_specified_date && !set_date)
483 /* Prepare to set system clock to the specified date/time
484 given in the POSIX-format. */
486 datestr = argv[optind];
487 valid_date = posixtime (&when.tv_sec,
490 | PDS_CENTURY | PDS_SECONDS));
491 when.tv_nsec = 0; /* FIXME: posixtime should set this. */
495 /* Prepare to print the current date/time. */
501 /* (option_specified_date || set_date) */
502 if (reference != NULL)
504 if (stat (reference, &refstats) != 0)
505 error (EXIT_FAILURE, errno, "%s", reference);
506 when = get_stat_mtime (&refstats);
511 datestr = set_datestr;
512 valid_date = get_date (&when, datestr, NULL);
517 error (EXIT_FAILURE, 0, _("invalid date %s"), quote (datestr));
521 /* Set the system clock to the specified date, then regardless of
522 the success of that operation, format and print that date. */
523 if (settime (&when) != 0)
525 error (0, errno, _("cannot set date"));
530 ok &= show_date (format, when);
533 exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
536 /* Display the date and/or time in WHEN according to the format specified
537 in FORMAT, followed by a newline. Return true if successful. */
540 show_date (const char *format, struct timespec when)
544 tm = localtime (&when.tv_sec);
547 char buf[INT_BUFSIZE_BOUND (intmax_t)];
548 error (0, 0, _("time %s is out of range"),
549 (TYPE_SIGNED (time_t)
550 ? imaxtostr (when.tv_sec, buf)
551 : umaxtostr (when.tv_sec, buf)));
555 if (format == rfc_2822_format)
556 setlocale (LC_TIME, "C");
557 fprintftime (stdout, format, tm, 0, when.tv_nsec);
558 fputc ('\n', stdout);
559 if (format == rfc_2822_format)
560 setlocale (LC_TIME, "");