1 /* date - print or set the system date and time
2 Copyright (C) 1989-2005 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 "fprintftime.h"
38 /* The official name of this program (e.g., no `g' prefix). */
39 #define PROGRAM_NAME "date"
41 #define AUTHORS "David MacKenzie"
45 static bool show_date (const char *format, struct timespec when);
49 /* Display only the date. */
51 /* Display date, hours, minutes, and seconds. */
53 /* Similar, but display nanoseconds. */
56 /* Put these last, since they aren't valid for --rfc-3339. */
58 /* Display date and hour. */
60 /* Display date, hours, and minutes. */
64 static char const *const time_spec_string[] =
66 /* Put "hours" and "minutes" first, since they aren't valid for
69 "date", "seconds", "ns", NULL
71 static enum Time_spec const time_spec[] =
73 TIME_SPEC_HOURS, TIME_SPEC_MINUTES,
74 TIME_SPEC_DATE, TIME_SPEC_SECONDS, TIME_SPEC_NS
76 ARGMATCH_VERIFY (time_spec_string, time_spec);
78 /* A format suitable for Internet RFC 2822. */
79 static char const rfc_2822_format[] = "%a, %d %b %Y %H:%M:%S %z";
81 /* The name this program was run with, for error messages. */
84 /* For long options that have no equivalent short option, use a
85 non-character as a pseudo short option, starting with CHAR_MAX + 1. */
88 RFC_3339_OPTION = CHAR_MAX + 1
91 static char const short_options[] = "d:f:I::r:Rs:u";
93 static struct option const long_options[] =
95 {"date", required_argument, NULL, 'd'},
96 {"file", required_argument, NULL, 'f'},
97 {"iso-8601", optional_argument, NULL, 'I'}, /* Deprecated. */
98 {"reference", required_argument, NULL, 'r'},
99 {"rfc-822", no_argument, NULL, 'R'},
100 {"rfc-2822", no_argument, NULL, 'R'},
101 {"rfc-3339", required_argument, NULL, RFC_3339_OPTION},
102 {"set", required_argument, NULL, 's'},
103 {"uct", no_argument, NULL, 'u'},
104 {"utc", no_argument, NULL, 'u'},
105 {"universal", no_argument, NULL, 'u'},
106 {GETOPT_HELP_OPTION_DECL},
107 {GETOPT_VERSION_OPTION_DECL},
112 # define TZSET tzset ()
114 # define TZSET /* empty */
118 # define DATE_FMT_LANGINFO() nl_langinfo (_DATE_FMT)
120 # define DATE_FMT_LANGINFO() ""
126 if (status != EXIT_SUCCESS)
127 fprintf (stderr, _("Try `%s --help' for more information.\n"),
132 Usage: %s [OPTION]... [+FORMAT]\n\
133 or: %s [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]\n\
135 program_name, program_name);
137 Display the current time in the given FORMAT, or set the system date.\n\
139 -d, --date=STRING display time described by STRING, not `now'\n\
140 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
143 -r, --reference=FILE display the last modification time of FILE\n\
144 -R, --rfc-2822 output date and time in RFC 2822 format\n\
145 --rfc-3339=TIMESPEC output date and time in RFC 3339 format.\n\
146 TIMESPEC=`date', `seconds', or `ns' for\n\
147 date and time to the indicated precision.\n\
148 -s, --set=STRING set time described by STRING\n\
149 -u, --utc, --universal print or set Coordinated Universal Time\n\
151 fputs (HELP_OPTION_DESCRIPTION, stdout);
152 fputs (VERSION_OPTION_DESCRIPTION, stdout);
155 FORMAT controls the output. The only valid option for the second form\n\
156 specifies Coordinated Universal Time. Interpreted sequences are:\n\
159 %a locale's abbreviated weekday name (e.g., Sun)\n\
162 %A locale's full weekday name (e.g., Sunday)\n\
163 %b locale's abbreviated month name (e.g., Jan)\n\
164 %B locale's full month name (e.g., January)\n\
165 %c locale's date and time (e.g., Thu Mar 3 23:05:25 2005)\n\
168 %C century; like %Y, except omit last two digits (e.g., 21)\n\
169 %d day of month (e.g, 01)\n\
170 %D date; same as %m/%d/%y\n\
171 %e day of month, space padded; same as %_d\n\
174 %F full date; same as %Y-%m-%d\n\
175 %g the last two digits of the year corresponding to the %V week number\n\
176 %G the year corresponding to the %V week number\n\
182 %j day of year (001..366)\n\
188 %M minute (00..59)\n\
192 %N nanoseconds (000000000..999999999)\n\
193 %p locale's equivalent of either AM or PM; blank if not known\n\
194 %P like %p, but lower case\n\
195 %r locale's 12-hour clock time (e.g., 11:11:04 PM)\n\
196 %R 24-hour hour and minute; same as %H:%M\n\
197 %s seconds since 1970-01-01 00:00:00 UTC\n\
200 %S second (00..60)\n\
202 %T time; same as %H:%M:%S\n\
203 %u day of week (1..7); 1 is Monday\n\
206 %U week number of year with Sunday as first day of week (00..53)\n\
207 %V week number of year with Monday as first day of week (01..53)\n\
208 %w day of week (0..6); 0 is Sunday\n\
209 %W week number of year with Monday as first day of week (00..53)\n\
212 %x locale's date representation (e.g., 12/31/99)\n\
213 %X locale's time representation (e.g., 23:13:48)\n\
214 %y last two digits of year (00..99)\n\
218 %z +hhmm numeric timezone (e.g., -0400)\n\
219 %:z +hh:mm numeric timezone (e.g., -04:00)\n\
220 %::z +hh:mm:ss numeric time zone (e.g., -04:00:00)\n\
221 %:::z numeric time zone with : to necessary precision (e.g., -04, +05:30)\n\
222 %Z alphabetic time zone abbreviation (e.g., EDT)\n\
224 By default, date pads numeric fields with zeroes.\n\
225 The following optional flags may follow `%':\n\
227 - (hyphen) do not pad the field\n\
228 _ (underscore) pad with spaces\n\
229 0 (zero) pad with zeros\n\
230 ^ use upper case if possible\n\
231 # use opposite case if possible\n\
235 After any flags comes an optional field width, as a decimal number;\n\
236 then an optional modifier, which is either\n\
237 E to use the locale's alternate representations if available, or\n\
238 O to use the locale's alternate numeric symbols if available.\n\
240 printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
245 /* Parse each line in INPUT_FILENAME as with --date and display each
246 resulting time and date. If the file cannot be opened, tell why
247 then exit. Issue a diagnostic for any lines that cannot be parsed.
248 Return true if successful. */
251 batch_convert (const char *input_filename, const char *format)
257 struct timespec when;
259 if (STREQ (input_filename, "-"))
261 input_filename = _("standard input");
266 in_stream = fopen (input_filename, "r");
267 if (in_stream == NULL)
269 error (EXIT_FAILURE, errno, "%s", quote (input_filename));
278 ssize_t line_length = getline (&line, &buflen, in_stream);
281 /* FIXME: detect/handle error here. */
285 if (! get_date (&when, line, NULL))
287 if (line[line_length - 1] == '\n')
288 line[line_length - 1] = '\0';
289 error (0, 0, _("invalid date %s"), quote (line));
294 ok &= show_date (format, when);
298 if (fclose (in_stream) == EOF)
299 error (EXIT_FAILURE, errno, "%s", quote (input_filename));
307 main (int argc, char **argv)
310 const char *datestr = NULL;
311 const char *set_datestr = NULL;
312 struct timespec when;
313 bool set_date = false;
314 char const *format = NULL;
315 char *batch_file = NULL;
316 char *reference = NULL;
317 struct stat refstats;
319 int option_specified_date;
321 initialize_main (&argc, &argv);
322 program_name = argv[0];
323 setlocale (LC_ALL, "");
324 bindtextdomain (PACKAGE, LOCALEDIR);
325 textdomain (PACKAGE);
327 atexit (close_stdout);
329 while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
332 char const *new_format = NULL;
342 case RFC_3339_OPTION:
344 static char const rfc_3339_format[][32] =
347 "%Y-%m-%d %H:%M:%S%:z",
348 "%Y-%m-%d %H:%M:%S.%N%:z"
351 XARGMATCH ("--rfc-3339", optarg,
352 time_spec_string + 2, time_spec + 2);
353 new_format = rfc_3339_format[i];
358 static char const iso_8601_format[][32] =
361 "%Y-%m-%dT%H:%M:%S%z",
362 "%Y-%m-%dT%H:%M:%S,%N%z",
368 ? XARGMATCH ("--iso-8601", optarg, time_spec_string, time_spec)
370 new_format = iso_8601_format[i];
377 new_format = rfc_2822_format;
380 set_datestr = optarg;
384 /* POSIX says that `date -u' is equivalent to setting the TZ
385 environment variable, so this option should do nothing other
387 if (putenv ("TZ=UTC0") != 0)
391 case_GETOPT_HELP_CHAR;
392 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
394 usage (EXIT_FAILURE);
400 error (EXIT_FAILURE, 0, _("multiple output formats specified"));
405 option_specified_date = ((datestr ? 1 : 0)
406 + (batch_file ? 1 : 0)
407 + (reference ? 1 : 0));
409 if (option_specified_date > 1)
412 _("the options to specify dates for printing are mutually exclusive"));
413 usage (EXIT_FAILURE);
416 if (set_date && option_specified_date)
419 _("the options to print and set the time may not be used together"));
420 usage (EXIT_FAILURE);
425 if (optind + 1 < argc)
427 error (0, 0, _("extra operand %s"), quote (argv[optind + 1]));
428 usage (EXIT_FAILURE);
431 if (argv[optind][0] == '+')
434 error (EXIT_FAILURE, 0, _("multiple output formats specified"));
435 format = argv[optind++] + 1;
437 else if (set_date || option_specified_date)
440 _("the argument %s lacks a leading `+';\n"
441 "When using an option to specify date(s), any non-option\n"
442 "argument must be a format string beginning with `+'."),
443 quote (argv[optind]));
444 usage (EXIT_FAILURE);
450 format = DATE_FMT_LANGINFO ();
453 /* Do not wrap the following literal format string with _(...).
454 For example, suppose LC_ALL is unset, LC_TIME="POSIX",
455 and LANG="ko_KR". In that case, POSIX says that LC_TIME
456 determines the format and contents of date and time strings
457 written by date, which means "date" must generate output
458 using the POSIX locale; but adding _() would cause "date"
459 to use a Korean translation of the format. */
460 format = "%a %b %e %H:%M:%S %Z %Y";
464 if (batch_file != NULL)
465 ok = batch_convert (batch_file, format);
468 bool valid_date = true;
471 if (!option_specified_date && !set_date)
475 /* Prepare to set system clock to the specified date/time
476 given in the POSIX-format. */
478 datestr = argv[optind];
479 valid_date = posixtime (&when.tv_sec,
482 | PDS_CENTURY | PDS_SECONDS));
483 when.tv_nsec = 0; /* FIXME: posixtime should set this. */
487 /* Prepare to print the current date/time. */
493 /* (option_specified_date || set_date) */
494 if (reference != NULL)
496 if (stat (reference, &refstats))
497 error (EXIT_FAILURE, errno, "%s", reference);
498 when.tv_sec = refstats.st_mtime;
499 when.tv_nsec = TIMESPEC_NS (refstats.st_mtim);
504 datestr = set_datestr;
505 valid_date = get_date (&when, datestr, NULL);
510 error (EXIT_FAILURE, 0, _("invalid date %s"), quote (datestr));
514 /* Set the system clock to the specified date, then regardless of
515 the success of that operation, format and print that date. */
516 if (settime (&when) != 0)
518 error (0, errno, _("cannot set date"));
523 ok &= show_date (format, when);
526 exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
529 /* Display the date and/or time in WHEN according to the format specified
530 in FORMAT, followed by a newline. If FORMAT is NULL, use the
531 standard output format (ctime style but with a timezone inserted).
532 Return true if successful. */
535 show_date (const char *format, struct timespec when)
539 tm = localtime (&when.tv_sec);
542 char buf[INT_BUFSIZE_BOUND (intmax_t)];
543 error (0, 0, _("time %s is out of range"),
544 (TYPE_SIGNED (time_t)
545 ? imaxtostr (when.tv_sec, buf)
546 : umaxtostr (when.tv_sec, buf)));
551 if (format == rfc_2822_format)
552 setlocale (LC_TIME, "C");
553 fprintftime (stdout, format, tm, 0, when.tv_nsec);
554 fputc ('\n', stdout);
555 if (format == rfc_2822_format)
556 setlocale (LC_TIME, "");