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

NAME

       getdate() - convert a string to struct tm

SYNOPSIS

       #define _XOPEN_SOURCE
       #define _XOPEN_SOURCE_EXTENDED
       #include <time.h>

       struct tm *getdate (const char *string);

       extern int getdate_err;

       #define _GNU_SOURCE
       #include <time.h>

       int getdate_r (const char *string, struct tm *res);

DESCRIPTION

       The  function  getdate()  converts  a string pointed to by string into the tm structure that it returns.  This tm structure may be found in
       static storage, so that it will be overwritten by the next call.

       In contrast to strptime(3), (which has a format argument), getdate() uses the formats found in the file of which  the  full  path  name	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 accepted:

       %Z     Timezone name.

       When %Z is given, the value to be returned is initialised to the broken-down time corresponding to the current time in the given time zone.
       Otherwise, it is initialised to the broken-down time corresponding to the current local time.

       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.

RETURN VALUE

       When  successful,  this	function  returns  a pointer to a struct tm.  Otherwise, it returns NULL and sets the global variable getdate_err.
       Changes to errno are unspecified.  The following values for getdate_err are defined:

       1   The DATEMSK environment variable is null or undefined.

       2   The template file cannot be opened for reading.

       3   Failed to get file status information.

       4   The template file is not a regular file.

       5   An error is 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.

NOTES

       Since getdate() is not reentrant because of the use of getdate_err and the static buffer to return the result in, glibc provides a  thread-
       safe  variant.	The  functionality is the same.  The result is returned in the buffer pointed to by res and in case of an error the return
       value is nonzero with the same values as given above for getdate_err.

       The POSIX 1003.1-2001 specification for strptime() contains conversion specifications using the %E or %O modifier,  while  such	specifica-
       tions are not given for getdate().  The glibc implementation implements getdate() using strptime() so that automatically precisely the same
       conversions are supported by both.

       The glibc implementation does not support the %Z conversion specification.

ENVIRONMENT

       DATEMSK
	      File containing format patterns.

       TZ, LC_TIME
	      Variables used by strptime().

CONFORMING TO

       ISO 9899, POSIX 1003.1-2001

SEE ALSO

       localtime(3), strftime(3), strptime(3), time(3)

								    2001-12-26								GETDATE(3)