GETDATE(category12-datenbank-server.html) - phpMan

GETDATE(3)                 Linux Programmer's Manual                GETDATE(3)

NAME
       getdate,  getdate_r  -  convert  a date-plus-time string to broken-down
       time
SYNOPSIS
       #include <time.h>
       struct tm *getdate(const char *string);
       extern int getdate_err;
       #include <time.h>
       int getdate_r(const char *string, struct tm *res);
   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
       getdate():
           _XOPEN_SOURCE >= 500 || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
       getdate_r():
           _GNU_SOURCE
DESCRIPTION
       The function getdate() converts a string representation of a  date  and
       time,  contained in the buffer pointed to by string, into a broken-down
       time.  The broken-down time is stored in a tm structure, and a  pointer
       to  this  structure is returned as the function result.  This tm struc-
       ture is allocated in static storage, and consequently it will be  over-
       written by further calls to getdate().
       In  contrast  to  strptime(3), (which has a format argument), getdate()
       uses the formats found in the file whose full pathname is given in  the
       environment  variable DATEMSK.  The first line in the file that matches
       the given input string is used for the conversion.
       The matching  is  done  case  insensitively.   Superfluous  whitespace,
       either in the pattern or in the string to be converted, is ignored.
       The  conversion  specifications  that  a  pattern can contain are those
       given for strptime(3).  One more conversion specification is  specified
       in POSIX.1-2001:
       %Z     Timezone name.  This is not implemented in glibc.
       When %Z is given, the structure containing the broken-down time is ini-
       tialized with values corresponding to the current  time  in  the  given
       timezone.   Otherwise,  the structure is initialized to the broken-down
       time corresponding to the current local time (as by a  call  to  local-
       time(3)).
       When  only  the weekday is given, the day is taken to be the first such
       day on or after today.
       When only the month is given (and no year), the month is  taken  to  be
       the first such month equal to or after the current month.  If no day is
       given, it is the first day of the month.
       When no hour, minute and second are given, the current hour, minute and
       second are taken.
       If  no  date is given, but we know the hour, then that hour is taken to
       be the first such hour equal to or after the current hour.
       getdate_r() is a GNU extension that provides  a  reentrant  version  of
       getdate().   Rather than using a global variable to report errors and a
       static buffer to return the broken down time, it returns errors via the
       function  result  value,  and returns the resulting broken-down time in
       the caller-allocated buffer pointed to by the argument res.
RETURN VALUE
       When successful, getdate() returns a pointer to a  struct  tm.   Other-
       wise,  it  returns NULL and sets the global variable getdate_err to one
       of the error numbers shown below.  Changes to errno are unspecified.
       On success getdate_r() returns 0; on error it returns one of the  error
       numbers shown below.
ERRORS
       The following errors are returned via getdate_err (for getdate()) or as
       the function result (for getdate_r()):
       1   The DATEMSK environment variable is not defined, or its value is an
           empty string.
       2   The  template  file specified by DATEMSK cannot be opened for read-
           ing.
       3   Failed to get file status information.
       4   The template file is not a regular file.
       5   An error was encountered while reading the template file.
       6   Memory allocation failed (not enough memory available).
       7   There is no line in the file that matches the input.
       8   Invalid input specification.
ENVIRONMENT
       DATEMSK
              File containing format patterns.
       TZ, LC_TIME
              Variables used by strptime(3).
ATTRIBUTES
   Multithreading (see pthreads(7))
       The getdate() function is not thread-safe.
       The getdate_r() function is thread-safe.
CONFORMING TO
       POSIX.1-2001.
NOTES
       The POSIX.1-2001  specification  for  strptime(3)  contains  conversion
       specifications  using  the %E or %O modifier, while such specifications
       are not given for getdate().  In glibc, getdate() is implemented  using
       strptime(3),  so  that  precisely the same conversions are supported by
       both.
EXAMPLE
       The program below calls getdate() for each of  its  command-line  argu-
       ments,  and  for  each  call  displays  the values in the fields of the
       returned tm structure.  The following shell  session  demonstrates  the
       operation of the program:
           $ TFILE=$PWD/tfile
           $ echo '%A' > $TFILE       # Full weekday name
           $ echo '%T' >> $TFILE      # ISO date (YYYY-MM-DD)
           $ echo '%F' >> $TFILE      # Time (HH:MM:SS)
           $ date
           $ export DATEMSK=$TFILE
           $ ./a.out Tuesday '2009-12-28' '12:22:33'
           Sun Sep  7 06:03:36 CEST 2008
           Call 1 ("Tuesday") succeeded:
               tm_sec   = 36
               tm_min   = 3
               tm_hour  = 6
               tm_mday  = 9
               tm_mon   = 8
               tm_year  = 108
               tm_wday  = 2
               tm_yday  = 252
               tm_isdst = 1
           Call 2 ("2009-12-28") succeeded:
               tm_sec   = 36
               tm_min   = 3
               tm_hour  = 6
               tm_mday  = 28
               tm_mon   = 11
               tm_year  = 109
               tm_wday  = 1
               tm_yday  = 361
               tm_isdst = 0
           Call 3 ("12:22:33") succeeded:
               tm_sec   = 33
               tm_min   = 22
               tm_hour  = 12
               tm_mday  = 7
               tm_mon   = 8
               tm_year  = 108
               tm_wday  = 0
               tm_yday  = 250
               tm_isdst = 1
   Program source
       #define _GNU_SOURCE 500
       #include <time.h>
       #include <stdio.h>
       #include <stdlib.h>
       int
       main(int argc, char *argv[])
       {
           struct tm *tmp;
           int j;
           for (j = 1; j < argc; j++) {
               tmp = getdate(argv[j]);
               if (tmp == NULL) {
                   printf("Call %d failed; getdate_err = %d\n",
                          j, getdate_err);
                   continue;
               }
               printf("Call %d (\"%s\") succeeded:\n", j, argv[j]);
               printf("    tm_sec   = %d\n", tmp->tm_sec);
               printf("    tm_min   = %d\n", tmp->tm_min);
               printf("    tm_hour  = %d\n", tmp->tm_hour);
               printf("    tm_mday  = %d\n", tmp->tm_mday);
               printf("    tm_mon   = %d\n", tmp->tm_mon);
               printf("    tm_year  = %d\n", tmp->tm_year);
               printf("    tm_wday  = %d\n", tmp->tm_wday);
               printf("    tm_yday  = %d\n", tmp->tm_yday);
               printf("    tm_isdst = %d\n", tmp->tm_isdst);
           }
           exit(EXIT_SUCCESS);
       }
SEE ALSO
       time(2), localtime(3), setlocale(3), strftime(3), strptime(3)
COLOPHON
       This  page  is  part of release 3.53 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

                                  2013-06-21                        GETDATE(3)