locate簡介及用法

標籤：linux

簡介

locate命令用於尋找檔案，Locate可以很快速的搜尋檔案系統內是否有指定的檔案。其方法是先建立一個包括系統內所有設定檔名稱及路徑的資料庫，之後當尋找時就只需查詢這個資料庫，而不必實際深入檔案系統之中了。所以它需要一個資料庫(預設:slocate.db)，一個設定檔(updatedb.conf)，一個crontab(定時執行) 

• 先運行updatedb, 可直接命令執行，也可以放在crontab裡面執行
• 然後在產生的/var/lib/slocate/slocate.db資料庫中尋找。

所以

• locate的速度比find快，因為它並不是真的尋找檔案，而是查資料庫
• locate的尋找並不是即時的，而是以資料庫的更新為準，一般是系統自己維護.
• locate的升級資料庫命令：locate -- u   #注意之間有空格

# ls -lart mlocate.db                    #更新前
-rw-r----- 1 root slocate 1286901 Aug  8 03:23 mlocate.db
# updatedb
# ls -lart mlocate.db                    #更新後
-rw-r----- 1 root slocate 1296268 Aug  8 11:10 mlocate.db


用法
# locate -S           //-->查看統計資訊，目錄，檔案，位元數適用情況

Database /var/lib/mlocate/mlocate.db:    3,315 directories    37,228 files    1,504,439 bytes in file names    594,851 bytes used to store database

# locate -V          //-->查看版本資訊  

<pre name="code" class="plain">mlocate 0.22.2Copyright (C) 2007 Red Hat, Inc. All rights reserved.This software is distributed under the GPL v.2.This program is provided with NO WARRANTY, to the extent permitted by law.

# locate -h          //-->查看協助資訊    

Usage: locate [OPTION]... [PATTERN]...Search for entries in a mlocate database.  -b, --basename         match only the base name of path names  -c, --count            only print number of found entries  -d, --database DBPATH  use DBPATH instead of default database (which is                         /var/lib/mlocate/mlocate.db)  -e, --existing         only print entries for currently existing files  -L, --follow           follow trailing symbolic links when checking file                         existence (default)  -h, --help             print this help  -i, --ignore-case      ignore case distinctions when matching patterns  -l, --limit, -n LIMIT  limit output (or counting) to LIMIT entries  -m, --mmap             ignored, for backward compatibility  -P, --nofollow, -H     don't follow trailing symbolic links when checking file                         existence  -0, --null             separate entries with NUL on output  -S, --statistics       don't search for entries, print statistics about each                         used database  -q, --quiet            report no error messages about reading databases  -r, --regexp REGEXP    search for basic regexp REGEXP instead of patterns      --regex            patterns are extended regexps  -s, --stdio            ignored, for backward compatibility  -V, --version          print version information  -w, --wholename        match whole path name (default)

# locate /etc/sh           //-->尋找/etc/sh*

/etc/shadow/etc/shadow-/etc/shadow.bup/etc/shadow.bup.20140725-214324/etc/shells

# locate -n 5 apache       //-->只找帶有apache目錄，顯示其中5行

/etc/selinux/targeted/modules/active/modules/apache.pp/opt/cpf/oma/3rdparty/apache-tomcat/opt/cpf/oma/3rdparty/apache-tomcat/LICENSE/opt/cpf/oma/3rdparty/apache-tomcat/NOTICE/opt/cpf/oma/3rdparty/apache-tomcat/RELEASE-NOTES

# locate -r makefile$      //-->尋找結尾為makefile的檔案目錄

/usr/share/doc/bcel-5.2/verifier/GNUmakefile

# locate -n 3 -r  ^\/opt   //-->尋找以/opt開頭的目錄，且只顯示3行

/opt/opt/cpf/opt/oss

#locate -i /HTTP           //-->尋找/HTTP目錄，忽略大小寫

/usr/share/perl5/Net/HTTP/NB.pm/usr/share/perl5/URI/http.pm/usr/share/perl5/URI/https.pm

# locate -c httpd.conf     //-->統計尋找到的數量 

3

# cat /etc/updatedb.conf   //-->設定檔

PRUNE_BIND_MOUNTS = "yes"PRUNEFS="9p afs anon_inodefs auto autofs bdev binfmt_misc cgroup cifs coda configfs cpuset debugfs devpts ecryptfs exofs fuse fusectl gfs gfs2 hugetlbfs inotifyfs iso9660 jffs2 lustre mqueue ncpfs nfs nfs4 nfsd pipefs proc ramfs rootfs rpc_pipefs securityfs selinuxfs sfs sockfs sysfs tmpfs ubifs udf usbfs efs100 lofs"PRUNENAMES = ".git .hg .svn"PRUNEPATHS = "/afs /media /net /sfs /tmp /udev /var/cache/ccache/var/spool/cups /var/spool/squid /var/tmp"PRUNEPATHS="/efs /efsroots"export PRUNEPATHS