Searching a file in linux
which
- We can use which command to find and get absolute path of files that are present in directories listed in PATH variable.
- We generally use which command to get absolute path of bash commands; since the directories to which they belong are listed in PATH variable.
-
Usage
which <file/command name>[root@localhost myDirectory]# echo $PATH /usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin [root@localhost myDirectory]# which uname /bin/uname [root@localhost myDirectory]#
locate
- We can use which command to find a file by its name.
- Issue with “locate” command is that it fetches data from mlocate database.
- So its necessary to update its database.
-
Usage
locate <file name>[root@localhost myDirectory]# locate noname.txt /home/noname.txt /root/noname.txt [root@localhost myDirectory]# updatedb [root@localhost myDirectory]# locate noname.txt /etc/noname.txt /home/noname.txt /myDirectory/noname.txt /root/noname.txt [root@localhost myDirectory]# -
To update mlocate database
updatedb
find
To find a file by name
To find a file by name in current directory
find -name "<file name>"
[root@localhost noname]# touch /home/noname.txt
[root@localhost noname]# touch noname.txt
[root@localhost noname]#
[root@localhost noname]# find -name "noname.txt"
./noname.txt
[root@localhost noname]# ls -l
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
[root@localhost noname]#
Note
Find command searches based on the case of file name given as input, if we want find to ignore case, we should use -iname flag
find -iname "<file name>"
[root@localhost noname]# ls -l
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:48 Noname.txt
[root@localhost noname]# find -name "noname.txt"
./noname.txt
[root@localhost noname]# find -iname "noname.txt"
./noname.txt
./Noname.txt
[root@localhost noname]#
To find a file by name in a specific directory
find <path> -name "<file name>"
[root@localhost noname]# find -name "noname.txt"
./noname.txt
[root@localhost noname]# find / -name "noname.txt"
find: ‘/run/user/1000/gvfs’: Permission denied
/root/noname.txt
/home/noname.txt
/noname/noname.txt
[root@localhost noname]#
To find a file that matches a particular pattern, like a file with extension .txt or .log
find <path> -name "<pattern>"
[root@localhost myDirectory]# ls -l /myDirectory
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:52 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -name "*.txt"
/myDirectory/noname.txt
/myDirectory/yahoo.txt
[root@localhost myDirectory]#
To find everything except a particular file
find <path> -not -name "<file name>"
[root@localhost myDirectory]# ls -l /myDirectory
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:52 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -not -name "noname.txt"
/myDirectory
/myDirectory/yahoo.txt
[root@localhost myDirectory]#
Note
Here, instead of file, we can also use a pattern, if we want to find all the files, except the one’s which matches a specific patten.
find <path> -not -name "<pattern>"
[root@localhost myDirectory]# ls -l /myDirectory
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:52 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -not -name "*.txt"
/myDirectory
/myDirectory/google
[root@localhost myDirectory]#
To find a file by type
Tip
Some common file types are
| c | character file |
| f | file |
| d | directory |
| l | symbolic links |
find <path> -type <type>
[root@localhost myDirectory]# ln -sf noname.txt noname_link
[root@localhost myDirectory]# pwd
/myDirectory
[root@localhost myDirectory]# ll
total 0
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:52 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -type l
/myDirectory/noname_link
[root@localhost myDirectory]#
To find a file by size
To find files of a particular size
find <path> -size <size>
[root@localhost myDirectory]# ls -l /myDirectory
total 4
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 57 Jan 4 12:10 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -size 10c
/myDirectory/noname_link
[root@localhost myDirectory]#
To find files of size greater than a certain size
find <path> -size +<size>
[root@localhost myDirectory]# ls -l /myDirectory
total 4
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 57 Jan 4 12:10 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -size +10c
/myDirectory
/myDirectory/yahoo.txt
[root@localhost myDirectory]#
To find files of size less than a certain size
find <path> -size -<size>
[root@localhost myDirectory]# ls -l /myDirectory
total 4
-rw-r--r--. 1 root root 0 Jan 4 11:54 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 root root 57 Jan 4 12:10 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -size -10c
/myDirectory/noname.txt
/myDirectory/google
[root@localhost myDirectory]#
To find a file by time
To find a file based on modified time
-
To find files that were modified certain days ago
find <path> -mtime <time in days>To find files which were modified exactly before 36 days.
[root@localhost myDirectory]# find / -mtime 36 /usr/bin/xmlwf /usr/lib64/libexpat.so.1.6.0 /usr/share/man/man1/xmlwf.1.gz [root@localhost myDirectory]# stat /usr/bin/xmlwf File: ‘/usr/bin/xmlwf’ Size: 24568 Blocks: 48 IO Block: 4096 regular file Device: fd00h/64768d Inode: 67184977 Links: 1 Access: (0755/-rwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) Context: system_u:object_r:bin_t:s0 Access: 2016-11-29 03:56:58.000000000 +0530 Modify: 2016-11-29 03:56:58.000000000 +0530 Change: 2016-12-26 11:21:20.003366643 +0530 Birth: - [root@localhost myDirectory]# date Wed Jan 4 13:27:03 IST 2017 [root@localhost myDirectory]# -
To find files with modified time less than certain days
find <path> -mtime -<time in days>To find files in /myDirectory which were modifies in less than one day.
[root@localhost myDirectory]# find /myDirectory -mtime -1 /myDirectory /myDirectory/noname.txt /myDirectory/google /myDirectory/noname_link /myDirectory/yahoo.txt [root@localhost myDirectory]# stat /myDirectory/noname_link File: ‘/myDirectory/noname_link’ -> ‘noname.txt’ Size: 10 Blocks: 0 IO Block: 4096 symbolic link Device: fd00h/64768d Inode: 202804770 Links: 1 Access: (0777/lrwxrwxrwx) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:default_t:s0 Access: 2017-01-04 12:02:28.798459580 +0530 Modify: 2017-01-04 12:02:27.726451168 +0530 Change: 2017-01-04 12:02:27.726451168 +0530 Birth: - [root@localhost myDirectory]# -
To find files with modified time more than certain days
find <path> -mtime +<time in days>To find files with modified time older than 3 days.
[root@localhost myDirectory]# [root@localhost myDirectory]# ls -l /myDirectory total 4 -rw-r--r--. 1 root root 0 Dec 31 02:05 google lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt -rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt -rw-r--r--. 1 root root 57 Jan 4 12:10 yahoo.txt [root@localhost myDirectory]# find /myDirectory -mtime +3 /myDirectory/google [root@localhost myDirectory]# stat /myDirectory/google File: ‘/myDirectory/google’ Size: 0 Blocks: 0 IO Block: 4096 regular empty file Device: fd00h/64768d Inode: 202804763 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:default_t:s0 Access: 2016-12-31 02:05:00.000000000 +0530 Modify: 2016-12-31 02:05:00.000000000 +0530 Change: 2017-01-04 13:38:27.420935829 +0530 Birth: - [root@localhost myDirectory]#
To find a file by access time
-
To find files that were accessed certain days ago
find <path> -atime <time in days>To find files which were accessed exactly before 36 days.
[root@localhost myDirectory]# find / -atime 36 /usr/bin/xmlwf [root@localhost myDirectory]# stat /usr/bin/xmlwf File: ‘/usr/bin/xmlwf’ Size: 24568 Blocks: 48 IO Block: 4096 regular file Device: fd00h/64768d Inode: 67184977 Links: 1 Access: (0755/-rwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) Context: system_u:object_r:bin_t:s0 Access: 2016-11-29 03:56:58.000000000 +0530 Modify: 2016-11-29 03:56:58.000000000 +0530 Change: 2016-12-26 11:21:20.003366643 +0530 Birth: - [root@localhost myDirectory]# -
To find files with access time less than certain days
find <path> -atime -<time in days>To find files in /myDirectory which were accessed in less than one day.
[root@localhost myDirectory]# find /myDirectory -atime -1 /myDirectory /myDirectory/noname.txt /myDirectory/noname_link /myDirectory/yahoo.txt [root@localhost myDirectory]# stat /myDirectory/noname_link File: ‘/myDirectory/noname_link’ -> ‘noname.txt’ Size: 10 Blocks: 0 IO Block: 4096 symbolic link Device: fd00h/64768d Inode: 202804770 Links: 1 Access: (0777/lrwxrwxrwx) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:default_t:s0 Access: 2017-01-04 12:02:28.798459580 +0530 Modify: 2017-01-04 12:02:27.726451168 +0530 Change: 2017-01-04 12:02:27.726451168 +0530 Birth: - [root@localhost myDirectory]# -
To find files with access time more than certain days
find <path> -atime +<time in days>To find files with access time older than 3 days.
[root@localhost myDirectory]# ls -l /myDirectory/ total 4 -rw-r--r--. 1 root root 0 Dec 31 02:05 google lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt -rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt -rw-r--r--. 1 root root 57 Jan 4 12:10 yahoo.txt [root@localhost myDirectory]# find /myDirectory -atime +3 /myDirectory/google [root@localhost myDirectory]# stat /myDirectory/google File: ‘/myDirectory/google’ Size: 0 Blocks: 0 IO Block: 4096 regular empty file Device: fd00h/64768d Inode: 202804763 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:default_t:s0 Access: 2016-12-31 02:05:00.000000000 +0530 Modify: 2016-12-31 02:05:00.000000000 +0530 Change: 2017-01-04 13:38:27.420935829 +0530 Birth: - [root@localhost myDirectory]#
To find files by user
find <path> -user <username>
[root@localhost myDirectory]# ls -l /myDirectory/
total 4
-rw-r--r--. 1 root root 0 Dec 31 02:05 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-rw-r--r--. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 suresh suresh 57 Jan 4 12:10 yahoo.txt
[root@localhost myDirectory]#
[root@localhost myDirectory]# find /myDirectory -user suresh
/myDirectory/yahoo.txt
[root@localhost myDirectory]# find /myDirectory -user root
/myDirectory
/myDirectory/noname.txt
/myDirectory/google
/myDirectory/noname_link
[root@localhost myDirectory]#
To find files by their permissions
find <path> -perm <permissions>
[root@localhost myDirectory]#
[root@localhost myDirectory]# ls -l /myDirectory
total 4
-rwxr-xr-x. 1 root root 0 Dec 31 02:05 google
lrwxrwxrwx. 1 root root 10 Jan 4 12:02 noname_link -> noname.txt
-r--------. 1 root root 0 Jan 4 11:44 noname.txt
-rw-r--r--. 1 suresh suresh 57 Jan 4 12:10 yahoo.txt
[root@localhost myDirectory]# find /myDirectory -perm 755
/myDirectory
/myDirectory/google
[root@localhost myDirectory]# find /myDirectory -perm 400
/myDirectory/noname.txt
[root@localhost myDirectory]#
To execute the command based on the files found
Tip
Here, {} refers to the files found by find commands. Please place {} properly as per command syntax.
find <path> <Other Conditions> -exec <command to be executed> {} \;
To find all the files with permission 400 and change their permission to 755.
[root@localhost myDirectory]#
[root@localhost myDirectory]# find /myDirectory -perm 400
/myDirectory/noname.txt
[root@localhost myDirectory]# ls -ld /myDirectory/noname.txt
-r--------. 1 root root 0 Jan 4 11:44 /myDirectory/noname.txt
[root@localhost myDirectory]# find /myDirectory -perm 400 -exec chmod 755 {} \;
[root@localhost myDirectory]# find /myDirectory -perm 400
[root@localhost myDirectory]# ls -ld /myDirectory/noname.txt
-rwxr-xr-x. 1 root root 0 Jan 4 11:44 /myDirectory/noname.txt
[root@localhost myDirectory]#
Note
We can also use pipe with the output generated by find and execute commands with those files as arguments.
find <path> <Other Conditions> | xargs -I {} <command to be executed> {}
[root@3a1b47b409f3 tmp]# find -mtime -1 | xargs -I {} ls -ld {}
drwxrwxrwt 1 root root 4096 Jun 13 23:39 .
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./b
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./d
drwxr-xr-x 2 root root 4096 Jun 13 23:39 ./s
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./f
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./a
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./c
-rw-r--r-- 1 root root 0 Jun 13 23:39 ./e
[root@3a1b47b409f3 tmp]#
[root@3a1b47b409f3 tmp]# find -mtime -1 | xargs -I {} rm {}
[root@3a1b47b409f3 tmp]#