date and time
有多个时间相关的设置，其中比较常用的是find和date，对于日志应用较多。
find的例子
其中find -mtime +0是昨天以前的文件，不包含昨天。
-atime n
File was last accessed n*24 hours ago. When find figures out how many 24-hour periods ago the
file was last accessed, any fractional part is ignored, so to match -atime +1, a file has to
have been accessed at least two days ago.
kk@ins14 /var/log $ ls -l | sort -k 6 | cat -n
1 total 16128
2 drwxrwsr-x 3 portage portage 4096 2014-08-14 15:09 portage
3 drwxrwx--- 2 root portage 4096 2014-08-14 15:40 sandbox
4 drwxr-xr-x 2 mysql mysql 4096 2014-08-18 21:15 mysql
5 drwxr-xr-x 2 root root 4096 2014-08-19 20:53 ConsoleKit
6 drwxr-xr-x 2 root root 4096 2014-08-19 21:10 samba
7 drwx------ 2 nginx nginx 4096 2014-08-28 12:49 nginx
8 -rw-r--r-- 1 root root 322727 2014-08-31 21:06 genkernel.log
9 -rw------- 1 root root 337 2014-09-10 10:03 ppp-connect-errors
10 drwxr-xr-x 2 root root 4096 2014-09-10 15:52 iptraf-ng
11 -rw-r----- 1 root adm 201237 2014-09-13 15:32 mail.err
12 drwxr-xr-x 2 root root 4096 2014-09-15 09:45 cups
13 drwxr-xr-x 2 tomcat tomcat 4096 2014-09-30 11:05 tomcat-7
14 drwxr-xr-x 2 root root 4096 2014-10-01 08:52 sa
15 drwxr-x--- 2 squid squid 4096 2014-10-02 18:07 squid
16 -rw-r----- 1 root adm 613125 2014-10-04 00:14 mail.info
17 -rw-r----- 1 root adm 613125 2014-10-04 00:14 mail.log
18 -rw-r----- 1 root adm 577554 2014-10-04 00:14 mail.warn
19 -rw-r----- 1 root adm 574235 2014-10-05 22:58 debug
20 -rw-r----- 1 root adm 4627369 2014-10-05 22:58 syslog
21 -rw-rw---- 1 portage portage 7440 2014-10-06 23:52 emerge-fetch.log
22 -rw-r----- 1 root adm 3161 2014-10-07 21:52 user.log
23 -rw-r----- 1 root root 25686 2014-10-08 08:53 dmesg
24 -rw-r--r-- 1 root root 187877 2014-10-08 08:53 rc.log
25 -rw-rw---- 1 portage portage 355270 2014-10-08 09:04 emerge.log
26 -rw-r----- 1 root adm 1655457 2014-10-08 11:23 kern.log
27 -rw-r----- 1 root adm 1338477 2014-10-08 11:23 messages
28 -rw-r----- 1 root adm 2464371 2014-10-08 13:34 daemon.log
29 -rw-r--r-- 1 root adm 86498 2014-10-08 13:34 debug.log
30 -rw-r--r-- 1 root root 292292 2014-10-08 13:38 lastlog
31 -rw------- 1 root root 64064 2014-10-08 13:38 tallylog
32 -rw-rw-r-- 1 root utmp 1383552 2014-10-08 13:38 wtmp
33 -rw-r----- 1 root adm 1272192 2014-10-08 13:40 auth.log
34 -rw-r--r-- 1 root adm 8800 2014-10-08 13:40 cron.log
kk@ins14 /var/log $ ls -l | sort -k 6 | cat -n^C
kk@ins14 /var/log $ find -maxdepth 1 -type f -mtime +0 | xargs ls --time-style=long-iso -l | sort -k 6 | cat -n
1 -rw-r--r-- 1 root root 0 2014-08-14 14:21 ./.keep
2 -rw-r--r-- 1 root root 322727 2014-08-31 21:06 ./genkernel.log
3 -rw------- 1 root root 337 2014-09-10 10:03 ./ppp-connect-errors
4 -rw-r----- 1 root adm 201237 2014-09-13 15:32 ./mail.err
5 -rw-r----- 1 root adm 613125 2014-10-04 00:14 ./mail.info
6 -rw-r----- 1 root adm 613125 2014-10-04 00:14 ./mail.log
7 -rw-r----- 1 root adm 577554 2014-10-04 00:14 ./mail.warn
8 -rw-r----- 1 root adm 574235 2014-10-05 22:58 ./debug
9 -rw-r----- 1 root adm 4627369 2014-10-05 22:58 ./syslog
10 -rw-rw---- 1 portage portage 7440 2014-10-06 23:52 ./emerge-fetch.log
date的例子
$ date
Wed Oct 8 13:46:45 CST 2014
$ date -d -1day
Tue Oct 7 13:46:52 CST 2014
$ date -d 1day
Thu Oct 9 13:46:55 CST 2014
$ date -d 3week
Wed Oct 29 13:47:02 CST 2014
$ date -d @1315167865
Mon Sep 5 04:24:25 CST 2011
$ date +%s
1415168070
touch的例子
kk@ins14 /tmp $ ls -l hp1000_linux.txt
-rw-r--r-- 1 kk kk 1223 2014-10-13 09:25 hp1000_linux.txt
kk@ins14 /tmp $ touch -t 11111111.11 hp1000_linux.txt
kk@ins14 /tmp $ ls -l hp1000_linux.txt
-rw-r--r-- 1 kk kk 1223 2014-11-11 11:11 hp1000_linux.txt
kk@ins14 /tmp $ touch -t 201111111111.11 hp1000_linux.txt
kk@ins14 /tmp $ ls -l hp1000_linux.txt
-rw-r--r-- 1 kk kk 1223 2011-11-11 11:11 hp1000_linux.txt
man一下touch的用法可以知道
-t STAMP
use [[CC]YY]MMDDhhmm[.ss] instead of current time
perl
- nginx的log如下：
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
127.0.0.1 - - [12/Nov/2014:15:47:20 +0800] "GET / HTTP/1.1" 200 1449 "-" "curl/7.39.0" "-"
perl -MPOSIX -nE 'BEGIN{$l=strftime "%T",localtime time - 3600 } if (/:(\S+?)\s/){print if $l lt $1}' /nginx/access.log
$ perl -MPOSIX -MDate::Parse -E 'say strftime "%F %T", localtime str2time"12/Nov/2014:15:47:20 +0800"'
2014-11-12 15:47:20
- emerge.log
$ sudo grep docker /var/log/emerge.log | perl -MPOSIX -npE 's/^\d+/strftime"%F_%T",localtime $&/e'
2019-03-30_00:05:48: >>> unmerge success: app-emulation/docker-proxy-0.8.0_p20181207
2019-03-30_00:05:50: === (1 of 6) Post-Build Cleaning (app-emulation/docker-proxy-0.8.0_p20190301::/usr/portage/app-emulation/docker-proxy/docker-proxy-0.8.0_p20190301.ebuild)
2019-03-30_00:05:50: ::: completed emerge (1 of 6) app-emulation/docker-proxy-0.8.0_p20190301 to /
2019-03-30_00:11:38: >>> emerge (6 of 6) app-emulation/docker-18.09.4 to /
2019-03-30_00:11:38: === (6 of 6) Cleaning (app-emulation/docker-18.09.4::/usr/portage/app-emulation/docker/docker-18.09.4.ebuild)
2019-03-30_00:11:38: === (6 of 6) Compiling/Merging (app-emulation/docker-18.09.4::/usr/portage/app-emulation/docker/docker-18.09.4.ebuild)
linux date command
# Get the seconds since epoch
date -d "Oct 21 1973" +%s
#Convert the number of seconds back to string
date -d @120024000