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>
42 static void show_date PARAMS ((const char *format, time_t when));
44 /* The name this program was run with, for error messages. */
47 /* If nonzero, display usage information and exit. */
50 /* If nonzero, print the version on standard output and exit. */
51 static int show_version;
53 /* If non-zero, display time in RFC-822 format for mail or news. */
54 static int rfc_format = 0;
56 /* If nonzero, print or set Coordinated Universal Time. */
57 static int universal_time = 0;
59 static struct option const long_options[] =
61 {"date", required_argument, NULL, 'd'},
62 {"file", required_argument, NULL, 'f'},
63 {"help", no_argument, &show_help, 1},
64 {"reference", required_argument, NULL, 'r'},
65 {"rfc-822", no_argument, NULL, 'R'},
66 {"set", required_argument, NULL, 's'},
67 {"uct", no_argument, NULL, 'u'},
68 {"utc", no_argument, NULL, 'u'},
69 {"universal", no_argument, NULL, 'u'},
70 {"version", no_argument, &show_version, 1},
74 #define TZ_UTC0 "TZ=UTC0"
77 # define TZSET tzset ()
79 # define TZSET /* empty */
82 #define MAYBE_SET_TZ_UTC0 \
83 do { if (universal_time) set_tz (TZ_UTC0); } while (0)
89 fprintf (stderr, _("Try `%s --help' for more information.\n"),
94 Usage: %s [OPTION]... [+FORMAT]\n\
95 or: %s [OPTION] [MMDDhhmm[[CC]YY][.ss]]\n\
97 program_name, program_name);
99 Display the current time in the given FORMAT, or set the system date.\n\
101 -d, --date=STRING display time described by STRING, not `now'\n\
102 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
103 -r, --reference=FILE display the last modification time of FILE\n\
104 -R, --rfc-822 output RFC-822 compliant date string\n\
105 -s, --set=STRING set time described by STRING\n\
106 -u, --utc, --universal print or set Coordinated Universal Time\n\
107 --help display this help and exit\n\
108 --version output version information and exit\n\
112 FORMAT controls the output. The only valid option for the second form\n\
113 specifies Coordinated Universal Time. Interpreted sequences are:\n\
116 %%a locale's abbreviated weekday name (Sun..Sat)\n\
117 %%A locale's full weekday name, variable length (Sunday..Saturday)\n\
118 %%b locale's abbreviated month name (Jan..Dec)\n\
119 %%B locale's full month name, variable length (January..December)\n\
120 %%c locale's date and time (Sat Nov 04 12:02:33 EST 1989)\n\
121 %%d day of month (01..31)\n\
122 %%D date (mm/dd/yy)\n\
123 %%e day of month, blank padded ( 1..31)\n\
127 %%j day of year (001..366)\n\
130 %%m month (01..12)\n\
131 %%M minute (00..59)\n\
133 %%p locale's AM or PM\n\
134 %%r time, 12-hour (hh:mm:ss [AP]M)\n\
135 %%s seconds since 00:00:00, Jan 1, 1970 (a GNU extension)\n\
136 %%S second (00..61)\n\
137 %%t a horizontal tab\n\
138 %%T time, 24-hour (hh:mm:ss)\n\
139 %%U week number of year with Sunday as first day of week (00..53)\n\
140 %%V week number of year with Monday as first day of week (01..52)\n\
141 %%w day of week (0..6); 0 represents Sunday\n\
142 %%W week number of year with Monday as first day of week (00..53)\n\
143 %%x locale's date representation (mm/dd/yy)\n\
144 %%X locale's time representation (%%H:%%M:%%S)\n\
145 %%y last two digits of year (00..99)\n\
146 %%Y year (1970...)\n\
147 %%z RFC-822 style numeric timezone (-0500) (a nonstandard extension)\n\
148 %%Z time zone (e.g., EDT), or nothing if no time zone is determinable\n\
150 By default, date pads numeric fields with zeroes. GNU date recognizes\n\
151 the following modifiers between `%%' and a numeric directive.\n\
153 `-' (hyphen) do not pad the field\n\
154 `_' (underscore) pad the field with spaces\n\
156 puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
161 /* Set the TZ environment variable. */
164 set_tz (const char *tz_eq_zone)
166 if (putenv (tz_eq_zone) != 0)
167 error (1, 0, "memory exhausted");
171 /* Parse each line in INPUT_FILENAME as with --date and display each
172 resulting time and date. If the file cannot be opened, tell why
173 then exit. Issue a diagnostic for any lines that cannot be parsed.
174 If any line cannot be parsed, return nonzero; otherwise return zero. */
177 batch_convert (const char *input_filename, const char *format)
188 /* Suppress `may be used before initialized' warning. */
192 if (strcmp (input_filename, "-") == 0)
194 input_filename = _("standard input");
199 in_stream = fopen (input_filename, "r");
200 if (in_stream == NULL)
202 error (1, errno, "`%s'", input_filename);
211 initial_TZ = getenv ("TZ");
212 if (initial_TZ == NULL)
214 initial_TZ = xstrdup ("TZ=");
218 size_t tz_len = strlen (initial_TZ);
219 char *buf = xmalloc (3 + tz_len + 1);
220 memcpy (mempcpy (buf, "TZ=", 3), initial_TZ, tz_len + 1);
228 line_length = getline (&line, &buflen, in_stream);
231 /* FIXME: detect/handle error here. */
237 /* When given a universal time option, restore the initial
238 value of TZ before parsing each string. */
242 when = get_date (line, NULL);
246 if (line[line_length - 1] == '\n')
247 line[line_length - 1] = '\0';
248 error (0, 0, _("invalid date `%s'"), line);
254 show_date (format, when);
260 if (fclose (in_stream) == EOF)
261 error (2, errno, input_filename);
270 main (int argc, char **argv)
273 const char *datestr = NULL;
274 const char *set_datestr = NULL;
278 char *batch_file = NULL;
279 char *reference = NULL;
280 struct stat refstats;
283 int option_specified_date;
285 program_name = argv[0];
286 setlocale (LC_ALL, "");
287 bindtextdomain (PACKAGE, LOCALEDIR);
288 textdomain (PACKAGE);
290 while ((optc = getopt_long (argc, argv, "d:f:r:Rs:u", long_options, NULL))
309 set_datestr = optarg;
321 printf ("date (%s) %s\n", GNU_PACKAGE, VERSION);
328 n_args = argc - optind;
330 option_specified_date = ((datestr ? 1 : 0)
331 + (batch_file ? 1 : 0)
332 + (reference ? 1 : 0));
334 if (option_specified_date > 1)
337 _("the options to specify dates for printing are mutually exclusive"));
341 if (set_date && option_specified_date)
344 _("the options to print and set the time may not be used together"));
350 error (0, 0, _("too many non-option arguments"));
354 if ((set_date || option_specified_date)
355 && n_args == 1 && argv[optind][0] != '+')
358 the argument `%s' lacks a leading `+';\n\
359 When using an option to specify date(s), any non-option\n\
360 argument must be a format string beginning with `+'."),
366 datestr = set_datestr;
368 if (batch_file != NULL)
370 status = batch_convert (batch_file,
371 (n_args == 1 ? argv[optind] + 1 : NULL));
377 if (!option_specified_date && !set_date)
379 if (n_args == 1 && argv[optind][0] != '+')
381 /* Prepare to set system clock to the specified date/time
382 given in the POSIX-format. */
384 datestr = argv[optind];
385 when = posixtime (datestr,
386 PDS_TRAILING_YEAR | PDS_CENTURY | PDS_SECONDS);
391 /* Prepare to print the current date/time. */
392 datestr = _("undefined");
394 format = (n_args == 1 ? argv[optind] + 1 : NULL);
399 /* (option_specified_date || set_date) */
400 if (reference != NULL)
402 if (stat (reference, &refstats))
403 error (1, errno, "%s", reference);
404 when = refstats.st_mtime;
408 when = get_date (datestr, NULL);
411 format = (n_args == 1 ? argv[optind] + 1 : NULL);
415 error (1, 0, _("invalid date `%s'"), datestr);
419 /* Set the system clock to the specified date, then regardless of
420 the success of that operation, format and print that date. */
421 if (stime (&when) == -1)
423 error (0, errno, _("cannot set date"));
428 /* When given a universal time option, set TZ to UTC0 after
429 parsing the specified date, but before printing it. */
432 show_date (format, when);
435 close_stdout_status (2);
440 /* Display the date and/or time in WHEN according to the format specified
441 in FORMAT, followed by a newline. If FORMAT is NULL, use the
442 standard output format (ctime style but with a timezone inserted). */
445 show_date (const char *format, time_t when)
449 size_t out_length = 0;
451 tm = localtime (&when);
455 /* Print the date in the default format. Vanilla ANSI C strftime
456 doesn't support %e, but POSIX requires it. If you don't use
457 a GNU strftime, make sure yours supports %e.
458 If you are not using GNU strftime, you want to change %z
459 in the RFC format to %Z; this gives, however, an invalid
460 RFC time format outside the continental United States and GMT. */
464 ? "%a, %_d %b %Y %H:%M:%S GMT"
465 : "%a, %_d %b %Y %H:%M:%S %z")
466 : "%a %b %e %H:%M:%S %Z %Y");
468 else if (*format == '\0')
477 out = (char *) xrealloc (out, out_length);
479 /* Mark the first byte of the buffer so we can detect the case
480 of strftime producing an empty string. Otherwise, this loop
481 would not terminate when date was invoked like this
482 `LANG=de date +%p' on a system with good language support. */
485 while (strftime (out, out_length, format, tm) == 0 && out[0] != '\0');
487 printf ("%s\n", out);