Problems with date cmd in terminal

[Browser_ice]

I am currently geting back to writing shell scripts. I am a bit rusty.

I am having problems with the date command. I am simply trying to store the date inside a variable. But to achieve this, I am playing with this command on the console with different options. One of which, doesn't seam to work. But according to its --help, it should. What am I doing wrong ?

browserice@Linux:~$ date --help
Usage: date [OPTION]... [+FORMAT]
or: date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]
Display the current time in the given FORMAT, or set the system date.

-d, --date=STRING display time described by STRING, not `now'
...

browserice@Linux:~$ date -d=%d/%m/%y
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d='%d/%m/%y'
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d="%d/%m/%y"
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d '%d%m%y'
date: invalid date `%d%m%y'
browserice@Linux:~$ date --date='%d/%m/%y'
date: invalid date `%d/%m/%y'
browserice@Linux:~$ date --date='%d%m%y'
date: invalid date `%d%m%y'

[wmcbrine]

-d lets you specify a different time, not a different format.

What you're looking for is '+'.

wmcbrine@alanis:~$ date +%d/%m/%y
28/06/06
wmcbrine@alanis:~$ date -d tomorrow
Thu Jun 29 15:47:42 EDT 2006

[FroL_Onn]

-d lets you specify a different time, not a different format.

What you're looking for is '+'.

wmcbrine@alanis:~$ date +%d/%m/%y
28/06/06
wmcbrine@alanis:~$ date -d tomorrow
Thu Jun 29 15:47:42 EDT 2006

Thanks a lot! This helped me!)

[howefield]

Old thread closed.

[Browser_ice]

Then why does the "man date" specifies otherwise ?

Is there a problem of command description versions in the "man" cmd ?

NAME
date - print or set the system date and time

SYNOPSIS
date [OPTION]... [+FORMAT]
date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]

DESCRIPTION
Display the current time in the given FORMAT, or set the system date.

-d, --date=STRING
display time described by STRING, not ‘now’

-f, --file=DATEFILE
like --date once for each line of DATEFILE

-r, --reference=FILE
display the last modification time of FILE

-R, --rfc-2822
output date and time in RFC 2822 format

--rfc-3339=TIMESPEC
output date and time in RFC 3339 format. TIMESPEC=‘date’, ‘sec‐
onds’, or ‘ns’ for date and time to the indicated precision.

-s, --set=STRING
set time described by STRING

-u, --utc, --universal
print or set Coordinated Universal Time

--help display this help and exit

--version
output version information and exit

FORMAT controls the output. The only valid option for the second form
specifies Coordinated Universal Time. Interpreted sequences are:

%% a literal %

%a locale’s abbreviated weekday name (e.g., Sun)

%A locale’s full weekday name (e.g., Sunday)

%b locale’s abbreviated month name (e.g., Jan)

%B locale’s full month name (e.g., January)

%c locale’s date and time (e.g., Thu Mar 3 23:05:25 2005)

%C century; like %Y, except omit last two digits (e.g., 21)

%d day of month (e.g, 01)

%D date; same as %m/%d/%y

%e day of month, space padded; same as %_d

%F full date; same as %Y-%m-%d

%g the last two digits of the year corresponding to the %V week
number

%G the year corresponding to the %V week number

%h same as %b

%H hour (00..23)

%I hour (01..12)

%j day of year (001..366)

%k hour ( 0..23)

%l hour ( 1..12)

%m month (01..12)

%M minute (00..59)

%n a newline

%N nanoseconds (000000000..999999999)

%p locale’s equivalent of either AM or PM; blank if not known

%P like %p, but lower case

%r locale’s 12-hour clock time (e.g., 11:11:04 PM)

%R 24-hour hour and minute; same as %H:%M

%s seconds since 1970-01-01 00:00:00 UTC

%S second (00..60)

%t a tab

%T time; same as %H:%M:%S

%u day of week (1..7); 1 is Monday

%U week number of year with Sunday as first day of week (00..53)

%V week number of year with Monday as first day of week (01..53)

%w day of week (0..6); 0 is Sunday

%W week number of year with Monday as first day of week (00..53)

%x locale’s date representation (e.g., 12/31/99)

%X locale’s time representation (e.g., 23:13:48)

%y last two digits of year (00..99)

%Y year

%z +hhmm numeric timezone (e.g., -0400)

%:z +hh:mm numeric timezone (e.g., -04:00)

%::z +hh:mm:ss numeric time zone (e.g., -04:00:00) %:::z numeric
time zone with : to necessary precision (e.g., -04, +05:30) %Z
alphabetic time zone abbreviation (e.g., EDT)

By default, date pads numeric fields with zeroes. The following
optional flags may follow ‘%’:

- (hyphen) do not pad the field _ (underscore) pad with spaces 0
(zero) pad with zeros ^ use upper case if possible # use oppo‐
site case if possible

After any flags comes an optional field width, as a decimal number;
then an optional modifier, which is either E to use the locale’s alter‐
nate representations if available, or O to use the locale’s alternate
numeric symbols if available.

AUTHOR
Written by David MacKenzie.

REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.

COPYRIGHT
Copyright © 2005 Free Software Foundation, Inc.
This is free software. You may redistribute copies of it under the
terms of the GNU General Public License
<http://www.gnu.org/licenses/gpl.html>. There is NO WARRANTY, to the
extent permitted by law.

SEE ALSO
The full documentation for date is maintained as a Texinfo manual. If
the info and date programs are properly installed at your site, the
command

info date

should give you access to the complete manual.

[wmcbrine]

Then why does the "man date" specifies otherwise ?

It doesn't. You're misreading it.

[Arndt]

I am currently geting back to writing shell scripts. I am a bit rusty.

I am having problems with the date command. I am simply trying to store the date inside a variable. But to achieve this, I am playing with this command on the console with different options. One of which, doesn't seam to work. But according to its --help, it should. What am I doing wrong ?

browserice@Linux:~$ date --help
Usage: date [OPTION]... [+FORMAT]
or: date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]
Display the current time in the given FORMAT, or set the system date.

-d, --date=STRING display time described by STRING, not `now'
...

browserice@Linux:~$ date -d=%d/%m/%y
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d='%d/%m/%y'
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d="%d/%m/%y"
date: invalid date `=%d/%m/%y'
browserice@Linux:~$ date -d '%d%m%y'
date: invalid date `%d%m%y'
browserice@Linux:~$ date --date='%d/%m/%y'
date: invalid date `%d/%m/%y'
browserice@Linux:~$ date --date='%d%m%y'
date: invalid date `%d%m%y'

"date --help" says, among other things (and I hate programs which react to -h by just telling me to use --help)

  -d, --date=STRING         display time described by STRING, not `now'

Here are some examples:

$ date --date=2004-05-06
Thu May  6 00:00:00 CEST 2004
$ date -d 2004-05-06
Thu May  6 00:00:00 CEST 2004
$ date -d=2004-05-06
date: invalid date `=2004-05-06'
$ date -d 05/06/04
Thu May  6 00:00:00 CEST 2004
$ date -d05/06/04
Thu May  6 00:00:00 CEST 2004

I might also misunderstand the description "time described by STRING", but when they contrast it with "now", I think the description is OK.

By the way, note among the above examples that "-d=2004-05-06" is not correct usage. It's usually only the -- options that use the equals sign. The older - options mostly do not.