Writing in the front

Find is used frequently in Linux daily management, and proficiency in it can be very productive.

The syntax of find is simple, and there are only a few common parameters, such as -name, -type, -ctime, etc. For starters, look directly at the examples in Part 2, and refer to the find help documentation for more information about the parameters.

Find syntax is as follows:

Find (option)(parameter)

Common examples

Search by filename

Lists all files in the current directory and subdirectories

find .
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Find the file named 11.png in the current directory

find . -name "11.png"
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Find all JPG files in the current directory

find . -name "*.jpg"
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Find JPG and PNG files in the current directory

find . -name "*.jpg" -o -name "*.png"
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Find files in the current directory that do not end in PNG

find . ! -name "*.png"
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Search by regular expression

Note: Regular representations are more complex than originally thought, supporting several types. You can refer to it here

Find PNG files with numeric names in the current directory.

find . -regex "\./*[0-9]+\.png" 
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Search by path

Find the file/path that contains WYSIWYg in the current directory.

find . -path "*wysiwyg*"
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Search by file type

The value of type is used to filter file types.

  • F Common files
  • L sign connection
  • D directory
  • C character device
  • B block device
  • S a socket
  • p Fifo

For example, find the files that contain WYSIWYG in the path of the current directory

find . -type f -path "*wysiwyg*"
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Limit search depth

Find all PNGS in the current directory, not subdirectories.

find . -maxdepth 1 -name "*.png"
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The corresponding minDepth option.

find . -mindepth 2 -maxdepth 2 -name "*.png"
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Based on file size

Filter file size by -size. The supported file size units are as follows

  • B — Block (512 bytes)
  • C – byte
  • W — word (2 bytes)
  • K — kilobytes
  • M — megabytes
  • G — gigabytes

For example, find files in the current directory that are larger than 100 MB

find . -type f -size +100M 
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Based on access/modification/change time

The following time types are supported.

  • Access time (-atime/ day, -amin/ min) : indicates the last access time.
  • Modification time (-mtime/ day, -mmin/ minute) : indicates the time when a file is last modified.
  • Change time (-ctime/ day, -cmin/ minute) : indicates the time when file data elements (such as permissions) are modified for the last time.

For example, find the files that have been modified within 1 day

find . -type f -mtime -1
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Find the files that have been accessed in the last 1 week

find . -type f -atime -7
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Move the log files that are more than a week old to/TMP /old_logs.

find . -type f -mtime +7 -name "*.log" -exec mv {} /tmp/old_logs \;
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Note: {} is used in conjunction with the -exec option to match all files and is then replaced with the appropriate filename.

In addition, \; Indicates the end of the command. If the command is not added, the following message is displayed

find: -exec: no terminating ";" or "+"
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According to the authority

This is done by -perm. For example, find the file whose permission is 777 in the current directory

find . -type f -perm 777
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Find PHP files in the current directory that are not 644 privileges

find . -type f -name "*.php" ! -perm 644
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According to the file owner

Find the file whose owner is root

find . -type f -user root
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Locate the file whose group is root

find . -type f -group root
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Execute the command when the file is found

-ok, and -exec. The difference is that -ok does a double check before executing the command, while -exec does not.

Let’s look at a real example. Delete all js files in the current directory. The effect of -ok is as follows, with a double check before deleting

➜ find find. -type f-name"*.js" -ok rm {} \;
"rm ./1.js"? 
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Try – exec. I just deleted it

find . -type f -name "*.js" -exec rm {} \;
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Finding empty files

Examples are as follows

touch {1.9}.txt
echo "hello" > 1.txt
find . -empty
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