getdate(3C) LIBRARY 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
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getdate(3C) LIBRARY FUNCTIONS getdate(3C)
%w weekday number ( Sunday = 0 - 6)
%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(3C).
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
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getdate(3C) LIBRARY FUNCTIONS getdate(3C)
_______________________________________________
| | |
The fo
|llowing rules are applied f
|or converting the
| input
specif
|ication into the internal fo
|rmat: |
| | |
I
|f only the weekday is given,
| today is assumed |if the
g
|iven day is equal to the cu
|rrent day and next|week if
i
|t is less. | |
| | |
I
|f only the month is given
|, the current mo
|nth is
a
|ssumed if the given mont
|h is equal to the|current
m
|onth and next year if it is|less and no year is
| given.
(
|The first day of month is as
|sumed if no day is|given.)
| | |
I
|f no hour, minute, and secon
|d are given, the |current
h
|our, minute, and second are|assumed. |
| | |
I
|f no date is given, today is
| assumed if the gi↓en hour
i
|s greater than the curre
|nt hour and tomo
|rrow is
a
|ssumed if it is less. | |
| | |
The fo
|llowing examples illustrate|the above rules. | Assume
that |the current date is Mon Se
|p 22 12:19:47 EDT 1
|986 and
the LANG environment variable is n
|ot set. |
_______|___________________________|__________________|_________
| Inpu
|t | Line in Template| | Date | |
|_______|_____|__________________|__|__________________|________|
| Mon | | %a | M
|on Sep 22 12:19:48|EDT 1986|
| Sun | | %a | S
|un Sep 28 12:19:49|EDT 1986|
| Fri | | %a | F
|ri Sep 26 12:19:49|EDT 1986|
| September | %B | M
|on Sep 1 12:19:49|EDT 1986|
| January | %B | T
|hu Jan 1 12:19:49|EST 1987|
| December | %B | M
|on Dec 1 12:19:49|EST 1986|
| Sep Mon | %b %a | M
|on Sep 1 12:19:50|EDT 1986|
| Jan Fri | %b %a | F
|ri Jan 2 12:19:50|EST 1987|
| Dec Mon | %b %a | M
|on Dec 1 12:19:50|EST 1986|
| Jan Wed 1989| %b %a %Y | W
|ed Jan 4 12:19:51|EST 1989|
| Fri 9 | | %a %H | F
|ri Sep 26 09:00:00|EDT 1986|
| Feb 10:30 | %b %H:%S | S
|un Feb 1 10:00:30|EST 1987|
| 10:30 | | %H:%M | T
|ue Sep 23 10:30:00|EDT 1986|
| 13:30 | | %H:%M | M
|on Sep 22 13:30:00|EDT 1986|
|_______|_____|__________________|__|__________________|________|
| | |
FILES | | |
/usr/lib/locale/<locale>/LCTIMEla
|nguage specific pr
|intable
files| | |
/usr/lib/locale/<locale>/LCCTYPEcode set specific printable
files
SEE ALSO
setlocale(3C), ctype(3C), environ(5).
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getdate(3C) LIBRARY FUNCTIONS getdate(3C)
DIAGNOSTICS
On failure getdate returns NULL and sets the variable
getdateerr to indicate the error.
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).
NOTES
Subsequent calls to getdate(3C) alter the contents of
getdateerr. Dates before 1970 and after 2037 are illegal.
getdate makes explicit use of macros described in ctype(3C).
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