1 /* date - print or set the system date and time
2 Copyright (C) 1989-2002 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18 David MacKenzie <djm@gnu.ai.mit.edu> */
23 #include <sys/types.h>
25 # include <langinfo.h>
36 /* The official name of this program (e.g., no `g' prefix). */
37 #define PROGRAM_NAME "date"
39 #define AUTHORS "David MacKenzie"
49 static void show_date PARAMS ((const char *format, time_t when));
53 /* display only the date: 1999-03-25 */
55 /* display date and hour: 1999-03-25T03-0500 */
57 /* display date, hours, and minutes: 1999-03-25T03:23-0500 */
59 /* display date, hours, minutes, and seconds: 1999-03-25T03:23:14-0500 */
63 static char const *const time_spec_string[] =
65 "date", "hours", "minutes", "seconds", 0
68 static enum Time_spec const time_spec[] =
70 TIME_SPEC_DATE, TIME_SPEC_HOURS, TIME_SPEC_MINUTES, TIME_SPEC_SECONDS
73 /* The name this program was run with, for error messages. */
76 /* If nonzero, display an ISO 8601 format date/time string */
77 static int iso_8601_format = 0;
79 /* If non-zero, display time in RFC-(2)822 format for mail or news. */
80 static int rfc_format = 0;
82 static struct option const long_options[] =
84 {"date", required_argument, NULL, 'd'},
85 {"file", required_argument, NULL, 'f'},
86 {"iso-8601", optional_argument, NULL, 'I'},
87 {"reference", required_argument, NULL, 'r'},
88 {"rfc-822", no_argument, NULL, 'R'},
89 {"set", required_argument, NULL, 's'},
90 {"uct", no_argument, NULL, 'u'},
91 {"utc", no_argument, NULL, 'u'},
92 {"universal", no_argument, NULL, 'u'},
93 {GETOPT_HELP_OPTION_DECL},
94 {GETOPT_VERSION_OPTION_DECL},
99 # define TZSET tzset ()
101 # define TZSET /* empty */
105 # define DATE_FMT_LANGINFO() nl_langinfo (_DATE_FMT)
107 # define DATE_FMT_LANGINFO() ""
114 fprintf (stderr, _("Try `%s --help' for more information.\n"),
119 Usage: %s [OPTION]... [+FORMAT]\n\
120 or: %s [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]\n\
122 program_name, program_name);
124 Display the current time in the given FORMAT, or set the system date.\n\
126 -d, --date=STRING display time described by STRING, not `now'\n\
127 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
128 -I, --iso-8601[=TIMESPEC] output an ISO-8601 compliant date/time string.\n\
129 TIMESPEC=`date' (or missing) for date only,\n\
130 `hours', `minutes', or `seconds' for date and\n\
131 time to the indicated precision.\n\
134 -r, --reference=FILE display the last modification time of FILE\n\
135 -R, --rfc-822 output RFC-822 compliant date string\n\
136 -s, --set=STRING set time described by STRING\n\
137 -u, --utc, --universal print or set Coordinated Universal Time\n\
139 fputs (HELP_OPTION_DESCRIPTION, stdout);
140 fputs (VERSION_OPTION_DESCRIPTION, stdout);
143 FORMAT controls the output. The only valid option for the second form\n\
144 specifies Coordinated Universal Time. Interpreted sequences are:\n\
147 %a locale's abbreviated weekday name (Sun..Sat)\n\
150 %A locale's full weekday name, variable length (Sunday..Saturday)\n\
151 %b locale's abbreviated month name (Jan..Dec)\n\
152 %B locale's full month name, variable length (January..December)\n\
153 %c locale's date and time (Sat Nov 04 12:02:33 EST 1989)\n\
156 %C century (year divided by 100 and truncated to an integer) [00-99]\n\
157 %d day of month (01..31)\n\
158 %D date (mm/dd/yy)\n\
159 %e day of month, blank padded ( 1..31)\n\
162 %F same as %Y-%m-%d\n\
163 %g the 2-digit year corresponding to the %V week number\n\
164 %G the 4-digit year corresponding to the %V week number\n\
170 %j day of year (001..366)\n\
176 %M minute (00..59)\n\
180 %p locale's upper case AM or PM indicator\n\
181 %P locale's lower case am or pm indicator\n\
182 %r time, 12-hour (hh:mm:ss [AP]M)\n\
183 %R time, 24-hour (hh:mm)\n\
184 %s seconds since `00:00:00 1970-01-01 UTC' (a GNU extension)\n\
187 %S second (00..60)\n\
188 %t a horizontal tab\n\
189 %T time, 24-hour (hh:mm:ss)\n\
190 %u day of week (1..7); 1 represents Monday\n\
193 %U week number of year with Sunday as first day of week (00..53)\n\
194 %V week number of year with Monday as first day of week (01..53)\n\
195 %w day of week (0..6); 0 represents Sunday\n\
196 %W week number of year with Monday as first day of week (00..53)\n\
199 %x locale's date representation (mm/dd/yy)\n\
200 %X locale's time representation (%H:%M:%S)\n\
201 %y last two digits of year (00..99)\n\
205 %z RFC-822 style numeric timezone (-0500) (a nonstandard extension)\n\
206 %Z time zone (e.g., EDT), or nothing if no time zone is determinable\n\
208 By default, date pads numeric fields with zeroes. GNU date recognizes\n\
209 the following modifiers between `%' and a numeric directive.\n\
211 `-' (hyphen) do not pad the field\n\
212 `_' (underscore) pad the field with spaces\n\
214 puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
219 /* Parse each line in INPUT_FILENAME as with --date and display each
220 resulting time and date. If the file cannot be opened, tell why
221 then exit. Issue a diagnostic for any lines that cannot be parsed.
222 If any line cannot be parsed, return nonzero; otherwise return zero. */
225 batch_convert (const char *input_filename, const char *format)
234 if (strcmp (input_filename, "-") == 0)
236 input_filename = _("standard input");
241 in_stream = fopen (input_filename, "r");
242 if (in_stream == NULL)
244 error (1, errno, "`%s'", input_filename);
253 line_length = getline (&line, &buflen, in_stream);
256 /* FIXME: detect/handle error here. */
260 when = get_date (line, NULL);
264 if (line[line_length - 1] == '\n')
265 line[line_length - 1] = '\0';
266 error (0, 0, _("invalid date `%s'"), line);
271 show_date (format, when);
275 if (fclose (in_stream) == EOF)
276 error (2, errno, "`%s'", input_filename);
285 main (int argc, char **argv)
288 const char *datestr = NULL;
289 const char *set_datestr = NULL;
293 char *batch_file = NULL;
294 char *reference = NULL;
295 struct stat refstats;
298 int option_specified_date;
300 program_name = argv[0];
301 setlocale (LC_ALL, "");
302 bindtextdomain (PACKAGE, LOCALEDIR);
303 textdomain (PACKAGE);
305 close_stdout_set_status (2);
306 atexit (close_stdout);
308 while ((optc = getopt_long (argc, argv, "d:f:I::r:Rs:u", long_options, NULL))
321 iso_8601_format = (optarg
322 ? XARGMATCH ("--iso-8601", optarg,
323 time_spec_string, time_spec)
333 set_datestr = optarg;
337 /* POSIX says that `date -u' is equivalent to setting the TZ
338 environment variable, so this option should do nothing other
340 if (putenv ("TZ=UTC0") != 0)
344 case_GETOPT_HELP_CHAR;
345 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
350 n_args = argc - optind;
352 option_specified_date = ((datestr ? 1 : 0)
353 + (batch_file ? 1 : 0)
354 + (reference ? 1 : 0));
356 if (option_specified_date > 1)
359 _("the options to specify dates for printing are mutually exclusive"));
363 if (set_date && option_specified_date)
366 _("the options to print and set the time may not be used together"));
372 error (0, 0, _("too many non-option arguments: %s%s"),
373 argv[optind + 1], n_args == 2 ? "" : " ...");
377 if ((set_date || option_specified_date)
378 && n_args == 1 && argv[optind][0] != '+')
381 the argument `%s' lacks a leading `+';\n\
382 When using an option to specify date(s), any non-option\n\
383 argument must be a format string beginning with `+'."),
388 /* Simply ignore --rfc-822 if specified when setting the date. */
389 if (rfc_format && !set_date && n_args > 0)
392 _("a format string may not be specified when using\
393 the --rfc-822 (-R) option"));
398 datestr = set_datestr;
400 if (batch_file != NULL)
402 status = batch_convert (batch_file,
403 (n_args == 1 ? argv[optind] + 1 : NULL));
409 if (!option_specified_date && !set_date)
411 if (n_args == 1 && argv[optind][0] != '+')
413 /* Prepare to set system clock to the specified date/time
414 given in the POSIX-format. */
416 datestr = argv[optind];
417 when = posixtime (datestr,
418 PDS_TRAILING_YEAR | PDS_CENTURY | PDS_SECONDS);
423 /* Prepare to print the current date/time. */
424 datestr = _("undefined");
426 format = (n_args == 1 ? argv[optind] + 1 : NULL);
431 /* (option_specified_date || set_date) */
432 if (reference != NULL)
434 if (stat (reference, &refstats))
435 error (1, errno, "%s", reference);
436 when = refstats.st_mtime;
440 when = get_date (datestr, NULL);
443 format = (n_args == 1 ? argv[optind] + 1 : NULL);
447 error (1, 0, _("invalid date `%s'"), datestr);
451 /* Set the system clock to the specified date, then regardless of
452 the success of that operation, format and print that date. */
453 if (stime (&when) == -1)
455 error (0, errno, _("cannot set date"));
460 show_date (format, when);
466 /* Display the date and/or time in WHEN according to the format specified
467 in FORMAT, followed by a newline. If FORMAT is NULL, use the
468 standard output format (ctime style but with a timezone inserted). */
471 show_date (const char *format, time_t when)
475 size_t out_length = 0;
476 /* ISO 8601 formats. See below regarding %z */
477 static char const * const iso_format_string[] =
482 "%Y-%m-%dT%H:%M:%S%z"
485 tm = localtime (&when);
489 /* Print the date in the default format. Vanilla ANSI C strftime
490 doesn't support %e, but POSIX requires it. If you don't use
491 a GNU strftime, make sure yours supports %e.
492 If you are not using GNU strftime, you want to change %z
493 in the RFC format to %Z; this gives, however, an invalid
494 RFC time format outside the continental United States and GMT. */
497 format = "%a, %d %b %Y %H:%M:%S %z";
498 else if (iso_8601_format)
499 format = iso_format_string[iso_8601_format - 1];
502 char *date_fmt = DATE_FMT_LANGINFO ();
503 /* Do not wrap the following literal format string with _(...).
504 For example, suppose LC_ALL is unset, LC_TIME="POSIX",
505 and LANG="ko_KR". In that case, POSIX says that LC_TIME
506 determines the format and contents of date and time strings
507 written by date, which means "date" must generate output
508 using the POSIX locale; but adding _() would cause "date"
509 to use a Korean translation of the format. */
510 format = *date_fmt ? date_fmt : "%a %b %e %H:%M:%S %Z %Y";
513 else if (*format == '\0')
523 out = (char *) xrealloc (out, out_length);
525 /* Mark the first byte of the buffer so we can detect the case
526 of strftime producing an empty string. Otherwise, this loop
527 would not terminate when date was invoked like this
528 `LANG=de date +%p' on a system with good language support. */
532 setlocale (LC_ALL, "C");
534 done = (strftime (out, out_length, format, tm) || out[0] == '\0');
537 setlocale (LC_ALL, "");
543 printf ("%s\n", out);