[Reprint] Linux Find command

Reprinted from Http://www.jb51.net/os/RedHat/1307.html

The Linux Find command searches the directory structure for files and performs the specified actions .

The Linux Find command provides quite a lot of search criteria and is powerful. Because find has powerful features, it has a lot of options, most of which are worth taking the time to look at.

Even if the system contains a network file system (NFS), the Find command works equally well in the file system, and you only have the appropriate permissions.

When running a very resource-intensive find command, many people tend to put it in the background because it can take a long time to traverse a large file system (this refers to a file system with more than 30G bytes).

1. Command format:

· Find Pathname-option [-print] [-exec-ok command] {} \;

2. Command function:

Used to locate files in the file tree and to make corresponding processing

3. Command parameters:

The directory path that the Pathname:find command looks for. For example . Represents the current directory / represents the system root directory.
The-print:find command outputs the matched file to standard output.
The-exec:find command executes the shell command given by the parameter to the matching file. The corresponding command is in the form of ' command ' {} \;, note the space between {} and \;
-ok: The same as-exec, except that the shell command given by the parameter is executed in a more secure mode, prompting the user to determine whether to execute before executing each command.

4. Command options:

-name finds files by file name .
-perm to find files according to file permissions .
-prune Use this option to have the Find command not be found in the currently specified directory (that is, ignoring the specified directory) , and if the-depth option is used at the same time,-prune will be ignored by the Find command.
-user username search for files according to the owner of the file .
-group GroupName finds files according to the group to which the files belong .
-mtime-n +n to find files according to the file change time ,-n refers to n days or less, +n refers to n days ago Modify

-atime-n +n check access by file access time

-Ctime-n +n by file creation time to find files,-n refers to n days, +n refers to n days before the create

-nogroup     Find does not have a valid owning group file, that is, the group to which the file belongs does not exist in/etc/groups.
-nouser       Find no valid primary file, that is, the owner of the file does not exist in the/etc/passwd.
-newer file1! file2   Find change time file1 the new but file2 older files than files.
-type finds a file of a certain type, such as:
B-block device file.
D-Directory. The
C-character device file.
P-pipe file. The
L-Symbolic link file.
F-Normal file.
-size N[c]     finds files with file lengths of n blocks, with C , indicating file lengths in bytes .

-depth When looking for a file, first find the file in the current directory and then look it up in its subdirectories (so that the lookup finds the directory before entering the subdirectory )
-fstype Find files located in a file system of a certain type , file system Type Table configuration file--- /etc/fstab
-mount does not cross the file system mount point when locating files
-follow If the find command encounters a symbolic link file, it tracks to the file that the link points to.
-cpio Use the Cpio command on the matching files to back up these files to the tape device.

In addition, the following three differences:

-amin N Find the last n minutes of files accessed in the system
-atime N Find The last n*24 hour access file in the system

-cmin n Find files in the last n minutes of the system changed file status
-ctime n Find files that have changed file status in the last n*24 hours of the system

-mmin n Find files that have changed file data in the last N minutes of the system
-mtime n Find files that have changed file data for the last n*24 hours (n days) in the system

5. Usage examples:

1) Find files that have been modified within 48 hours

Find-atime-2

2) Find files with the file name ending with. Log in the current directory

Find . -name "*.log" # #. The number represents the search in the current directory

3) Find all files with permission 777 under the/opt/soft/test/directory

find/opt/soft/test/-perm 777

4) Find common files that end with. Log in the directory

Find. -type f-name "*.log"

5) Find and sort all current directories

Find. -type D | Sort

6) Find files with current directory larger than 1K

Find. -size +1000c-print

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Query command	Describe
Find ~-name "*.txt"-print	Check. txt files in home and show
Find. -name "*.txt"-print
Find. -name "[a-z]*"-print	Check for files that begin with a capital letter
Find/etc-name "host*"-print	Check for files that begin with host
Find. -name "[A-z][a-z][0–9][0–9].txt"-print	Find txt files with two lowercase letters and two numbers
Find. -perm 755-print	Find all files and directories in the current directory with file mode 777
Find. -perm-007-exec ls-l {} \;
Find. -type D-print	Print directory Structure
Find. ! -type D-print	Print non-catalog files
Find. -type L-print	Print a symbolic link file
Find. -size +1000000c-print Find. -size +1000k-exec ls-ld {};	Files with file lengths greater than 1M are checked
Find. -size 100c-print	Files with file lengths equal to 100c
Find/home-size +512k	Check for files larger than 512k
find/home-size-512k	Check for files smaller than 512k
Find. -size +10-print	Files with file lengths greater than 10 blocks No unit, thumb block (1 block = 512 bytes) Cell C, Bytes byte Unit k, refers to kilobytes (KB)
Find/etc-name "passwd"-exec grep "Cnscn" {} \;	See if there are CNSCN users
Find. -name "yao*" | Xargs file
Find. -name "yao*" | Xargs echo "" >/tmp/core.log
Find. -name "yao*" | Xargs chmod o-w
Find-name april*	Find files starting with April in the current directory
Find-name april* fprint File	Finds files starting with April in the current directory and outputs the results to file
Find-name ap*-o-name may*	Find files that start with an AP or May
Find/mnt-name Tom.txt-ftype VFAT	Find files with name Tom.txt and file system type VFAT under/MNT
Find/mnt-name T.txt! -ftype VFAT	Find files with name Tom.txt and file system type not VFAT under/mnt
Find/tmp-name wa*-type L	In/tmp, look for a file with a type of symbolic link that begins with the name WA
-mtime-n +n (-n refers to the nth day or less, +n refers to n days ago) eg:-mtime-6 +3 last 6 days 3 days ago -atime -ctime
Find/home-mtime +2	Under/home, check the files that were changed two days ago.
Find/home-mtime-2	Under/home, check the files that have been changed in the last two days
Find/home-mmin +60	Under/home, check the files that were changed 60 minutes ago.
Find/home-mmin-5	Under/home, find files that have been modified in the last 5 minutes
Find/home-atime-1	Under/home, check for files that have been accessed within 1 days
Find/home-atime-2	Under/home, find files accessed within 2 days (within the last 48 hours)
Find/home-used-2	Files or directories that have been accessed within 2nd
Find/home-amin +30	Under/home, check the files that were accessed 30 minutes ago
Find/home-amin-10	Under/home, find files accessed in the last 10 minutes
Find/home-newer Tmp.txt	Check the update time at/home than tmp.txt new file or directory
Find/home-anewer Tmp.txt	Check access time in/home to a newer file or directory than tmp.txt
Find/home-user CNSCN	List files or directories belonging to user CNSCN in the/home directory
Find/home-uid +501	Lists files or directories in the/home directory for users with identifiers greater than 501
Find/home-group CNSCN	List files or directories in/home with group CNSCN
Find/home-gid 501	List files or directories with group ID 501 in/home
Find/home-nouser	Lists files or directories in/home that are not local users
Find/home-nogroup	List files or directories in/home that do not belong to a local group
Find/home-name tmp.txt-maxdepth 4	List Tmp.txt in/home with a depth of up to 3 layers
Find/home-name tmp.txt-mindepth 3	Start with the 2nd floor.
Find/home-empty	Find a file size of 0 or an empty directory
Find/home-links +2	Files or directories with a hard connection number greater than 2

[Reprint] Linux Find command