1 /* date - print or set the system date and time
2 Copyright (C) 1989-1999 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>
33 /* The official name of this program (e.g., no `g' prefix). */
34 #define PROGRAM_NAME "date"
36 #define AUTHORS "David MacKenzie"
48 static void show_date PARAMS ((const char *format, time_t when));
52 /* display only the date: 1999-03-25 */
54 /* display date and hour: 1999-03-25T03-0500 */
56 /* display date, hours, and minutes: 1999-03-25T03:23-0500 */
58 /* display date, hours, minutes, and seconds: 1999-03-25T03:23:14-0500 */
62 static char const *const time_spec_string[] =
64 "date", "hours", "minutes", "seconds", 0
67 static enum Time_spec const time_spec[] =
69 TIME_SPEC_DATE, TIME_SPEC_HOURS, TIME_SPEC_MINUTES, TIME_SPEC_SECONDS
72 /* The name this program was run with, for error messages. */
75 /* If nonzero, display an ISO 8601 format date/time string */
76 static int iso_8601_format = 0;
78 /* If non-zero, display time in RFC-822 format for mail or news. */
79 static int rfc_format = 0;
81 /* If nonzero, print or set Coordinated Universal Time. */
82 static int universal_time = 0;
84 static struct option const long_options[] =
86 {"date", required_argument, NULL, 'd'},
87 {"file", required_argument, NULL, 'f'},
88 {"iso-8601", optional_argument, NULL, 'I'},
89 {"reference", required_argument, NULL, 'r'},
90 {"rfc-822", no_argument, NULL, 'R'},
91 {"set", required_argument, NULL, 's'},
92 {"uct", no_argument, NULL, 'u'},
93 {"utc", no_argument, NULL, 'u'},
94 {"universal", no_argument, NULL, 'u'},
95 {GETOPT_HELP_OPTION_DECL},
96 {GETOPT_VERSION_OPTION_DECL},
100 #define TZ_UTC0 "TZ=UTC0"
103 # define TZSET tzset ()
105 # define TZSET /* empty */
108 #define MAYBE_SET_TZ_UTC0 \
109 do { if (universal_time) set_tz (TZ_UTC0); } while (0)
115 fprintf (stderr, _("Try `%s --help' for more information.\n"),
120 Usage: %s [OPTION]... [+FORMAT]\n\
121 or: %s [OPTION] [MMDDhhmm[[CC]YY][.ss]]\n\
123 program_name, program_name);
125 Display the current time in the given FORMAT, or set the system date.\n\
127 -d, --date=STRING display time described by STRING, not `now'\n\
128 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
129 -I, --iso-8601[=TIMESPEC] output an ISO-8601 compliant date/time string.\n\
130 TIMESPEC=`date' (or missing) for date only,\n\
131 `hours', `minutes', or `seconds' for date and\n\
132 time to the indicated precision.\n\
133 -r, --reference=FILE display the last modification time of FILE\n\
134 -R, --rfc-822 output RFC-822 compliant date string\n\
135 -s, --set=STRING set time described by STRING\n\
136 -u, --utc, --universal print or set Coordinated Universal Time\n\
137 --help display this help and exit\n\
138 --version output version information and exit\n\
142 FORMAT controls the output. The only valid option for the second form\n\
143 specifies Coordinated Universal Time. Interpreted sequences are:\n\
146 %%a locale's abbreviated weekday name (Sun..Sat)\n\
147 %%A locale's full weekday name, variable length (Sunday..Saturday)\n\
148 %%b locale's abbreviated month name (Jan..Dec)\n\
149 %%B locale's full month name, variable length (January..December)\n\
150 %%c locale's date and time (Sat Nov 04 12:02:33 EST 1989)\n\
151 %%d day of month (01..31)\n\
152 %%D date (mm/dd/yy)\n\
153 %%e day of month, blank padded ( 1..31)\n\
157 %%j day of year (001..366)\n\
160 %%m month (01..12)\n\
161 %%M minute (00..59)\n\
163 %%p locale's AM or PM\n\
164 %%r time, 12-hour (hh:mm:ss [AP]M)\n\
165 %%s seconds since 00:00:00, Jan 1, 1970 (a GNU extension)\n\
166 %%S second (00..60)\n\
167 %%t a horizontal tab\n\
168 %%T time, 24-hour (hh:mm:ss)\n\
169 %%U week number of year with Sunday as first day of week (00..53)\n\
170 %%V week number of year with Monday as first day of week (01..52)\n\
171 %%w day of week (0..6); 0 represents Sunday\n\
172 %%W week number of year with Monday as first day of week (00..53)\n\
173 %%x locale's date representation (mm/dd/yy)\n\
174 %%X locale's time representation (%%H:%%M:%%S)\n\
175 %%y last two digits of year (00..99)\n\
176 %%Y year (1970...)\n\
177 %%z RFC-822 style numeric timezone (-0500) (a nonstandard extension)\n\
178 %%Z time zone (e.g., EDT), or nothing if no time zone is determinable\n\
180 By default, date pads numeric fields with zeroes. GNU date recognizes\n\
181 the following modifiers between `%%' and a numeric directive.\n\
183 `-' (hyphen) do not pad the field\n\
184 `_' (underscore) pad the field with spaces\n\
186 puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
191 /* Set the TZ environment variable. */
194 set_tz (const char *tz_eq_zone)
196 if (putenv (tz_eq_zone) != 0)
197 error (1, 0, "memory exhausted");
201 /* Parse each line in INPUT_FILENAME as with --date and display each
202 resulting time and date. If the file cannot be opened, tell why
203 then exit. Issue a diagnostic for any lines that cannot be parsed.
204 If any line cannot be parsed, return nonzero; otherwise return zero. */
207 batch_convert (const char *input_filename, const char *format)
215 char *initial_TZ IF_LINT (= NULL);
217 if (strcmp (input_filename, "-") == 0)
219 input_filename = _("standard input");
224 in_stream = fopen (input_filename, "r");
225 if (in_stream == NULL)
227 error (1, errno, "`%s'", input_filename);
236 initial_TZ = getenv ("TZ");
237 if (initial_TZ == NULL)
239 initial_TZ = xstrdup ("TZ=");
243 size_t tz_len = strlen (initial_TZ);
244 char *buf = xmalloc (3 + tz_len + 1);
245 memcpy (mempcpy (buf, "TZ=", 3), initial_TZ, tz_len + 1);
253 line_length = getline (&line, &buflen, in_stream);
256 /* FIXME: detect/handle error here. */
262 /* When given a universal time option, restore the initial
263 value of TZ before parsing each string. */
267 when = get_date (line, NULL);
271 if (line[line_length - 1] == '\n')
272 line[line_length - 1] = '\0';
273 error (0, 0, _("invalid date `%s'"), line);
279 show_date (format, when);
285 if (fclose (in_stream) == EOF)
286 error (2, errno, "`%s'", input_filename);
295 main (int argc, char **argv)
298 const char *datestr = NULL;
299 const char *set_datestr = NULL;
303 char *batch_file = NULL;
304 char *reference = NULL;
305 struct stat refstats;
308 int option_specified_date;
310 program_name = argv[0];
311 setlocale (LC_ALL, "");
312 bindtextdomain (PACKAGE, LOCALEDIR);
313 textdomain (PACKAGE);
315 while ((optc = getopt_long (argc, argv, "d:f:I::r:Rs:u", long_options, NULL))
328 iso_8601_format = (optarg
329 ? XARGMATCH ("--iso-8601", optarg,
330 time_spec_string, time_spec)
340 set_datestr = optarg;
346 case_GETOPT_HELP_CHAR;
347 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
352 n_args = argc - optind;
354 option_specified_date = ((datestr ? 1 : 0)
355 + (batch_file ? 1 : 0)
356 + (reference ? 1 : 0));
358 if (option_specified_date > 1)
361 _("the options to specify dates for printing are mutually exclusive"));
365 if (set_date && option_specified_date)
368 _("the options to print and set the time may not be used together"));
374 error (0, 0, _("too many non-option arguments"));
378 if ((set_date || option_specified_date)
379 && n_args == 1 && argv[optind][0] != '+')
382 the argument `%s' lacks a leading `+';\n\
383 When using an option to specify date(s), any non-option\n\
384 argument must be a format string beginning with `+'."),
390 datestr = set_datestr;
392 if (batch_file != NULL)
394 status = batch_convert (batch_file,
395 (n_args == 1 ? argv[optind] + 1 : NULL));
401 if (!option_specified_date && !set_date)
403 if (n_args == 1 && argv[optind][0] != '+')
405 /* Prepare to set system clock to the specified date/time
406 given in the POSIX-format. */
408 datestr = argv[optind];
409 when = posixtime (datestr,
410 PDS_TRAILING_YEAR | PDS_CENTURY | PDS_SECONDS);
415 /* Prepare to print the current date/time. */
416 datestr = _("undefined");
418 format = (n_args == 1 ? argv[optind] + 1 : NULL);
423 /* (option_specified_date || set_date) */
424 if (reference != NULL)
426 if (stat (reference, &refstats))
427 error (1, errno, "%s", reference);
428 when = refstats.st_mtime;
432 when = get_date (datestr, NULL);
435 format = (n_args == 1 ? argv[optind] + 1 : NULL);
439 error (1, 0, _("invalid date `%s'"), datestr);
443 /* Set the system clock to the specified date, then regardless of
444 the success of that operation, format and print that date. */
445 if (stime (&when) == -1)
447 error (0, errno, _("cannot set date"));
452 /* When given a universal time option, set TZ to UTC0 after
453 parsing the specified date, but before printing it. */
456 show_date (format, when);
459 close_stdout_status (2);
464 /* Display the date and/or time in WHEN according to the format specified
465 in FORMAT, followed by a newline. If FORMAT is NULL, use the
466 standard output format (ctime style but with a timezone inserted). */
469 show_date (const char *format, time_t when)
473 size_t out_length = 0;
474 /* ISO 8601 formats, in local and UTC. See below regarding %z */
475 static char *iso_format_string[5][2] =
478 {"%Y-%m-%d", "%Y-%m-%d"},
479 {"%Y-%m-%dT%H%z", "%Y-%m-%dT%HZ"},
480 {"%Y-%m-%dT%H:%M%z", "%Y-%m-%dT%H:%MZ"},
481 {"%Y-%m-%dT%H:%M:%S%z", "%Y-%m-%dT%H:%M:%SZ"}
484 tm = localtime (&when);
488 /* Print the date in the default format. Vanilla ANSI C strftime
489 doesn't support %e, but POSIX requires it. If you don't use
490 a GNU strftime, make sure yours supports %e.
491 If you are not using GNU strftime, you want to change %z
492 in the RFC format to %Z; this gives, however, an invalid
493 RFC time format outside the continental United States and GMT. */
497 ? "%a, %_d %b %Y %H:%M:%S GMT"
498 : "%a, %_d %b %Y %H:%M:%S %z")
500 ? iso_format_string[iso_8601_format][universal_time]
501 : "%a %b %e %H:%M:%S %Z %Y"));
503 else if (*format == '\0')
512 out = (char *) xrealloc (out, out_length);
514 /* Mark the first byte of the buffer so we can detect the case
515 of strftime producing an empty string. Otherwise, this loop
516 would not terminate when date was invoked like this
517 `LANG=de date +%p' on a system with good language support. */
520 while (strftime (out, out_length, format, tm) == 0 && out[0] != '\0');
522 printf ("%s\n", out);