1 /* date - print or set the system date and time
2 Copyright (C) 89, 90, 91, 92, 93, 94, 95, 96, 1997
3 Free Software Foundation, Inc.
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2, or (at your option)
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software Foundation,
17 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 David MacKenzie <djm@gnu.ai.mit.edu> */
24 #include <sys/types.h>
44 static void show_date __P ((const char *format, time_t when));
45 static void usage __P ((int status));
47 /* The name this program was run with, for error messages. */
50 /* If nonzero, display usage information and exit. */
53 /* If nonzero, print the version on standard output and exit. */
54 static int show_version;
56 /* If non-zero, display time in RFC-822 format for mail or news. */
57 static int rfc_format = 0;
59 /* If nonzero, print or set Coordinated Universal Time. */
60 static int universal_time = 0;
62 static struct option const long_options[] =
64 {"date", required_argument, NULL, 'd'},
65 {"file", required_argument, NULL, 'f'},
66 {"help", no_argument, &show_help, 1},
67 {"reference", required_argument, NULL, 'r'},
68 {"rfc-822", no_argument, NULL, 'R'},
69 {"set", required_argument, NULL, 's'},
70 {"uct", no_argument, NULL, 'u'},
71 {"utc", no_argument, NULL, 'u'},
72 {"universal", no_argument, NULL, 'u'},
73 {"version", no_argument, &show_version, 1},
77 #define TZ_UTC0 "TZ=UTC0"
80 # define TZSET tzset ()
82 # define TZSET /* empty */
85 #define MAYBE_SET_TZ_UTC0 \
86 do { if (universal_time) set_tz (TZ_UTC0); } while (0)
88 /* Set the TZ environment variable. */
91 set_tz (const char *tz_eq_zone)
93 if (putenv (tz_eq_zone) != 0)
94 error (1, 0, "memory exhausted");
98 /* Parse each line in INPUT_FILENAME as with --date and display each
99 resulting time and date. If the file cannot be opened, tell why
100 then exit. Issue a diagnostic for any lines that cannot be parsed.
101 If any line cannot be parsed, return nonzero; otherwise return zero. */
104 batch_convert (const char *input_filename, const char *format)
115 /* Suppress `may be used before initialized' warning. */
119 if (strcmp (input_filename, "-") == 0)
121 input_filename = _("standard input");
126 in_stream = fopen (input_filename, "r");
127 if (in_stream == NULL)
129 error (1, errno, "`%s'", input_filename);
138 initial_TZ = getenv ("TZ");
139 if (initial_TZ == NULL)
141 initial_TZ = xstrdup ("TZ=");
145 char *buf = xmalloc (3 + strlen (initial_TZ) + 1);
146 stpcpy (stpcpy (buf, "TZ="), initial_TZ);
154 line_length = getline (&line, &buflen, in_stream);
157 /* FIXME: detect/handle error here. */
163 /* When given a universal time option, restore the initial
164 value of TZ before parsing each string. */
168 when = get_date (line, NULL);
172 if (line[line_length - 1] == '\n')
173 line[line_length - 1] = '\0';
174 error (0, 0, _("invalid date ` %s'"), line);
180 show_date (format, when);
186 if (fclose (in_stream) == EOF)
187 error (2, errno, input_filename);
196 main (int argc, char **argv)
199 const char *datestr = NULL;
200 const char *set_datestr = NULL;
204 char *batch_file = NULL;
205 char *reference = NULL;
206 struct stat refstats;
209 int option_specified_date;
211 program_name = argv[0];
212 setlocale (LC_ALL, "");
213 bindtextdomain (PACKAGE, LOCALEDIR);
214 textdomain (PACKAGE);
216 while ((optc = getopt_long (argc, argv, "d:f:r:Rs:u", long_options, NULL))
235 set_datestr = optarg;
247 printf ("date (%s) %s\n", GNU_PACKAGE, VERSION);
254 n_args = argc - optind;
256 option_specified_date = ((datestr ? 1 : 0)
257 + (batch_file ? 1 : 0)
258 + (reference ? 1 : 0));
260 if (option_specified_date > 1)
263 _("the options to specify dates for printing are mutually exclusive"));
267 if (set_date && option_specified_date)
270 _("the options to print and set the time may not be used together"));
276 error (0, 0, _("too many non-option arguments"));
280 if ((set_date || option_specified_date)
281 && n_args == 1 && argv[optind][0] != '+')
284 the argument `%s' lacks a leading `+';\n\
285 When using an option to specify date(s), any non-option\n\
286 argument must be a format string beginning with `+'."),
292 datestr = set_datestr;
294 if (batch_file != NULL)
296 status = batch_convert (batch_file,
297 (n_args == 1 ? argv[optind] + 1 : NULL));
303 if (!option_specified_date && !set_date)
305 if (n_args == 1 && argv[optind][0] != '+')
307 /* Prepare to set system clock to the specified date/time
308 given in the POSIX-format. */
310 datestr = argv[optind];
311 when = posixtime (datestr);
316 /* Prepare to print the current date/time. */
317 datestr = _("undefined");
319 format = (n_args == 1 ? argv[optind] + 1 : NULL);
324 /* (option_specified_date || set_date) */
325 if (reference != NULL)
327 if (stat (reference, &refstats))
328 error (1, errno, "%s", reference);
329 when = refstats.st_mtime;
333 when = get_date (datestr, NULL);
336 format = (n_args == 1 ? argv[optind] + 1 : NULL);
340 error (1, 0, _("invalid date `%s'"), datestr);
344 /* Set the system clock to the specified date, then regardless of
345 the success of that operation, format and print that date. */
346 if (stime (&when) == -1)
347 error (0, errno, _("cannot set date"));
350 /* When given a universal time option, set TZ to UTC0 after
351 parsing the specified date, but before printing it. */
354 show_date (format, when);
357 if (fclose (stdout) == EOF)
358 error (2, errno, _("write error"));
363 /* Display the date and/or time in WHEN according to the format specified
364 in FORMAT, followed by a newline. If FORMAT is NULL, use the
365 standard output format (ctime style but with a timezone inserted). */
368 show_date (const char *format, time_t when)
372 size_t out_length = 0;
374 tm = localtime (&when);
378 /* Print the date in the default format. Vanilla ANSI C strftime
379 doesn't support %e, but POSIX requires it. If you don't use
380 a GNU strftime, make sure yours supports %e.
381 If you are not using GNU strftime, you want to change %z
382 in the RFC format to %Z; this gives, however, an invalid
383 RFC time format outside the continental United States and GMT. */
387 ? "%a, %_d %b %Y %H:%M:%S GMT"
388 : "%a, %_d %b %Y %H:%M:%S %z")
389 : "%a %b %e %H:%M:%S %Z %Y");
391 else if (*format == '\0')
400 out = (char *) xrealloc (out, out_length);
402 /* Mark the first byte of the buffer so we can detect the case
403 of strftime producing an empty string. Otherwise, this loop
404 would not terminate when date was invoked like this
405 `LANG=de date +%p' on a system with good language support. */
408 while (strftime (out, out_length, format, tm) == 0 && out[0] != '\0');
410 printf ("%s\n", out);
418 fprintf (stderr, _("Try `%s --help' for more information.\n"),
423 Usage: %s [OPTION]... [+FORMAT]\n\
424 or: %s [OPTION] [MMDDhhmm[[CC]YY][.ss]]\n\
426 program_name, program_name);
428 Display the current time in the given FORMAT, or set the system date.\n\
430 -d, --date=STRING display time described by STRING, not `now'\n\
431 -f, --file=DATEFILE like --date once for each line of DATEFILE\n\
432 -r, --reference=FILE display the last modification time of FILE\n\
433 -R, --rfc-822 output RFC-822 compliant date string\n\
434 -s, --set=STRING set time described by STRING\n\
435 -u, --utc, --universal print or set Coordinated Universal Time\n\
436 --help display this help and exit\n\
437 --version output version information and exit\n\
441 FORMAT controls the output. The only valid option for the second form\n\
442 specifies Coordinated Universal Time. Interpreted sequences are:\n\
445 %%a locale's abbreviated weekday name (Sun..Sat)\n\
446 %%A locale's full weekday name, variable length (Sunday..Saturday)\n\
447 %%b locale's abbreviated month name (Jan..Dec)\n\
448 %%B locale's full month name, variable length (January..December)\n\
449 %%c locale's date and time (Sat Nov 04 12:02:33 EST 1989)\n\
450 %%d day of month (01..31)\n\
451 %%D date (mm/dd/yy)\n\
452 %%e day of month, blank padded ( 1..31)\n\
456 %%j day of year (001..366)\n\
459 %%m month (01..12)\n\
460 %%M minute (00..59)\n\
462 %%p locale's AM or PM\n\
463 %%r time, 12-hour (hh:mm:ss [AP]M)\n\
464 %%s seconds since 00:00:00, Jan 1, 1970 (a GNU extension)\n\
465 %%S second (00..61)\n\
466 %%t a horizontal tab\n\
467 %%T time, 24-hour (hh:mm:ss)\n\
468 %%U week number of year with Sunday as first day of week (00..53)\n\
469 %%V week number of year with Monday as first day of week (01..52)\n\
470 %%w day of week (0..6); 0 represents Sunday\n\
471 %%W week number of year with Monday as first day of week (00..53)\n\
472 %%x locale's date representation (mm/dd/yy)\n\
473 %%X locale's time representation (%%H:%%M:%%S)\n\
474 %%y last two digits of year (00..99)\n\
475 %%Y year (1970...)\n\
476 %%z RFC-822 style numeric timezone (-0500) (a nonstandard extension)\n\
477 %%Z time zone (e.g., EDT), or nothing if no time zone is determinable\n\
479 By default, date pads numeric fields with zeroes. GNU date recognizes\n\
480 the following modifiers between `%%' and a numeric directive.\n\
482 `-' (hyphen) do not pad the field\n\
483 `_' (underscore) pad the field with spaces\n\
485 puts (_("\nReport bugs to <sh-utils-bugs@gnu.org>."));