cron裡面可以設定變數嗎 - Linux

※ 引述《[email protected] (Astro v.s. Geo)》之銘言：
: ※ 引述《[email protected] (閒泡菜)》之銘言：
: : 請問一下
: : 我想要用cron定時去執行指令，然後導向到文字檔裡面去
: : 然後那個文字檔的檔名可以用系統時間來命名嗎??
: : 例如這樣：
: : */3 * * * * 指令 > 系統時間.txt
: : 最後目錄會出現
: : 2010.05.01-17:00:00.txt
: : 2010.05.01-17:03:00.txt
: : 2010.05.01-17:06:00.txt
: : 依序的出現時間命名的檔案
: : 不知道可否做到可以設系統變數的方法??
: 很常用阿，幾乎每天都會用
: man一下date吧
DATE(1) User Commands DATE(1)

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 <[email protected]>.

COPYRIGHT
Copyright (C) 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.

date 5.93 October 2008 DATE(1)


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