curl_getdate(3) libcurl Manual curl_getdate(3)NAMEcurl_getdate - Convert an date string to number of seconds
since January 1, 1970
SYNOPSIS
#include <curl/curl.h>
time_t curl_getdate(char *datestring, time_t *now );
DESCRIPTION
This function returns the number of seconds since January
1st 1970 in the UTC time zone, for the date and time that
the datestring parameter specifies. The now parameter is not
used, pass a NULL there.
NOTE: This function was rewritten for the 7.12.2 release and
this documentation covers the functionality of the new one.
The new one is not feature-complete with the old one, but
most of the formats supported by the new one was supported
by the old too.
PARSING DATES AND TIMES
A "date" is a string containing several items separated by
whitespace. The order of the items is immaterial. A date
string may contain many flavors of items:
calendar date items
Can be specified several ways. Month names can only
be three-letter english abbrivations, numbers can be
zero-prefixed and the year may use 2 or 4 digits.
Examples: 06 Nov 1994, 06-Nov-94 and Nov-94 6.
time of the day items
This string specifies the time on a given day. You
must specify it with 6 digits with two colons:
HH:MM:SS. To not include the time in a date string,
will make the function assume 00:00:00. Example:
18:19:21.
time zone items
Specifies international time zone. There are a few
acronyms supported, but in general you should
instead use the specific relative time compared to
UTC. Supported formats include: -1200, MST, +0100.
day of the week items
Specifies a day of the week. Days of the week may be
spelled out in full (using english): `Sunday', `Mon-
day', etc or they may be abbreviated to their first
three letters. This is usually not info that adds
anything.
libcurl 7.0 Last change: 12 Aug 2005 1
curl_getdate(3) libcurl Manual curl_getdate(3)
pure numbers
If a decimal number of the form YYYYMMDD appears,
then YYYY is read as the year, MM as the month
number and DD as the day of the month, for the
specified calendar date.
EXAMPLES
Sun, 06 Nov 1994 08:49:37 GMT
Sunday, 06-Nov-94 08:49:37 GMT
Sun Nov 6 08:49:37 1994
06 Nov 1994 08:49:37 GMT
06-Nov-94 08:49:37 GMT
Nov 6 08:49:37 1994
06 Nov 1994 08:49:37
06-Nov-94 08:49:37
1994 Nov 6 08:49:37
GMT 08:49:37 06-Nov-94 Sunday
94 6 Nov 08:49:37
1994 Nov 6
06-Nov-94
Sun Nov 6 94
1994.Nov.6
Sun/Nov/6/94/GMT
Sun, 06 Nov 1994 08:49:37 CET
06 Nov 1994 08:49:37 EST
Sun, 12 Sep 2004 15:05:58 -0700
Sat, 11 Sep 2004 21:32:11 +0200
20040912 15:05:58 -0700
20040911 +0200
STANDARDS
This parser was written to handle date formats specified in
RFC 822 (including the update in RFC 1123) using time zone
name or time zone delta and RFC 850 (obsoleted by RFC 1036)
and ANSI C's asctime() format. These formats are the only
ones RFC2616 says HTTP applications may use.
RETURN VALUE
This function returns -1 when it fails to parse the date
string. Otherwise it returns the number of seconds as
described.
If the year is larger than 2037 on systems with 32 bit
time_t, this function will return 0x7fffffff (since that is
the largest possible signed 32 bit number).
Having a 64 bit time_t is not a guarantee that dates beyond
03:14:07 UTC, January 19, 2038 will work fine. On systems
with a 64 bit time_t but with a crippled mktime(),
curl_getdate will return -1 in this case.
libcurl 7.0 Last change: 12 Aug 2005 2
curl_getdate(3) libcurl Manual curl_getdate(3)REWRITE
The former version of this function was built with yacc and
was not only very large, it was also never quite understood
and it wasn't possible to build with non-GNU tools since
only GNU Bison could make it thread-safe!
The rewrite was done for 7.12.2. The new one is much smaller
and use simpler code.
libcurl 7.0 Last change: 12 Aug 2005 3
