getdate(3C) COMPATIBILITY FUNCTIONS getdate(3C)
NAME
getdate - convert user format date and time
SYNOPSIS
#include <time.h>
struct tm *getdate (const char *string);
extern int getdateerr;
DESCRIPTION
getdate converts user-definable date and/or time specifica-
tions pointed to by string into a tm structure. The struc-
ture declaration is in the time.h header file [see also
ctime(3C)].
User-supplied templates are used to parse and interpret the
input string. The templates are text files created by the
user and identified via the environment variable DATEMSK.
Each line in the template represents an acceptable date
and/or time specification using some of the same field
descriptors as the ones used by the date command. The first
line in the template that matches the input specification is
used for interpretation and conversion into the internal
time format. If successful, the function getdate returns a
pointer to a tm structure; otherwise, it returns NULL and
sets the global variable getdateerr to indicate the error.
The following field descriptors are supported:
%% same as %
%a abbreviated weekday name
%A full weekday name
%b abbreviated month name
%B full month name
%c locale's appropriate date and time representation
%d day of month (01-31; the leading 0 is optional)
%e same as %d
%D date as %m/%d/%y
%h abbreviated month name
%H hour (00-23)
%I hour (01-12)
%m month number (01-12)
%M minute (00-59)
%n same as \n
%p locale's equivalent of either AM or PM
%r time as %I:%M:%S %p
%R time as %H:%M
%S seconds (00-59)
%t insert a tab
%T time as %H:%M:%S
%w weekday number (0-6; Sunday = 0)
Last change: C Programming Language Utilities 1
getdate(3C) COMPATIBILITY FUNCTIONS getdate(3C)
%x locale's appropriate date representation
%X locale's appropriate time representation
%y year with century (00-99)
%Y year as ccyy (e.g., 1986)
%Z time zone name or no characters if no time zone
exists
The month and weekday names can consist of any combination
of upper and lower case letters. The user can request that
the input date or time specification be in a specific
language by setting the categories LCTIME and LCCTYPE of
setlocale.
The following example shows the possible contents of a tem-
plate:
%m
%A %B %d %Y, %H:%M:%S
%A
%B
%m/%d/%y %I %p
%d,%m,%Y %H:%M
at %A the %dst of %B in %Y
run job at %I %p,%B %dnd
%A den %d. %B %Y %H.%M Uhr
The following are examples of valid input specifications for
the above template:
getdate("10/1/87 4 PM")
getdate("Friday")
getdate("Friday September 19 1987, 10:30:30")
getdate("24,9,1986 10:30")
getdate("at monday the 1st of december in 1986")
getdate("run job at 3 PM, december %2nd")
If the LANG environment variable is set to german, the fol-
lowing is valid:
getdate("freitag den 10. oktober 1986 10.30 Uhr")
Local time and date specification are also supported. The
following examples show how local date and time specifica-
tion can be defined in the template.
_______________________________________________
|_________Invocation________|__Line_in_Template|
| getdate("11/27/86") | %m/%d/%y |
| getdate("27.11.86") | %d.%m.%y |
| getdate("86-11-27") | %y-%m-%d |
| getdate("Friday 12:00:00")| %A %H:%M:%S |
|___________________________|__________________|
Last change: C Programming Language Utilities 2
getdate(3C) COMPATIBILITY FUNCTIONS getdate(3C)
The following rules are applied for converting the input
specification into the internal format:
If only the weekday is given, today is assumed if the
given day is equal to the current day and next week if
it is less.
If only the month is given, the current month is
assumed if the given month is equal to the current
month and next year if it is less and no year is given.
(The first day of month is assumed if no day is given.)
If no hour, minute, and second are given, the current
hour, minute, and second are assumed.
If no date is given, today is assumed if the given hour
is greater than the current hour and tomorrow is
assumed if it is less.
The following examples illustrate the above rules. Assume
that the current date is Mon Sep 22 12:19:47 EDT 1986 and
the LANG environment variable is not set.
________________________________________________________________
|____Input____|__Line_in_Template|______________Date____________|
| Mon | %a | Mon Sep 22 12:19:48 EDT 1986|
| Sun | %a | Sun Sep 28 12:19:49 EDT 1986|
| Fri | %a | Fri Sep 26 12:19:49 EDT 1986|
| September | %B | Mon Sep 1 12:19:49 EDT 1986|
| January | %B | Thu Jan 1 12:19:49 EST 1987|
| December | %B | Mon Dec 1 12:19:49 EST 1986|
| Sep Mon | %b %a | Mon Sep 1 12:19:50 EDT 1986|
| Jan Fri | %b %a | Fri Jan 2 12:19:50 EST 1987|
| Dec Mon | %b %a | Mon Dec 1 12:19:50 EST 1986|
| Jan Wed 1989| %b %a %Y | Wed Jan 4 12:19:51 EST 1989|
| Fri 9 | %a %H | Fri Sep 26 09:00:00 EDT 1986|
| Feb 10:30 | %b %H:%S | Sun Feb 1 10:00:30 EST 1987|
| 10:30 | %H:%M | Tue Sep 23 10:30:00 EDT 1986|
| 13:30 | %H:%M | Mon Sep 22 13:30:00 EDT 1986|
|_____________|__________________|______________________________|
FILES
/usr/lib/locale/<locale>/LCTIMElanguage specific printable
files
/usr/lib/locale/<locale>/LCCTYPEcode set specific printable
files
SEE ALSO
setlocale(3C), ctype(3C), environ(5).
DIAGNOSTICS
On failure getdate returns NULL and sets the variable
getdateerr to indicate the error.
Last change: C Programming Language Utilities 3
getdate(3C) COMPATIBILITY FUNCTIONS getdate(3C)
The following is a complete list of the getdateerr settings
and their meanings.
1 The DATEMSK environment variable is null or unde-
fined.
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 malloc failed (not enough memory is available).
7 There is no line in the template that matches the
input.
8 The input specification is invalid (e.g., February
31).
Last change: C Programming Language Utilities 4
getdate(3C) COMPATIBILITY FUNCTIONS getdate(3C)
NOTES
Subsequent calls to getdate alter the contents of
getdateerr. Dates before 1970 and after 2037 are illegal.
getdate makes explicit use of macros described in ctype(3C).
Last change: C Programming Language Utilities 5