[find command] wont remember :v #linux

find.md

find can search for files/dirs in a dir hierarchy, based on various criteria such as name, type, size, time modified, ownership, ...

find PATH [OPTIONS] [EXPRESSIONS]

Some most common options

-name PATTERN: specify the name of the file/directory you want to search.

Note: dot . not represent a single character in this pattern?

Note 2: indeed, turns out:

• ? can match any single character except /.
• * can match any string of characters not containing / (includes matching an empty string)
• ** can match any string of characters. This includes matching an empty string, and / character. So it recurses into subdirectories.

-type [dfl]: specify the type of the file, there are many types but you only need to remember:

• d: directory
• f: regular file
• l: symbolic link

-size: Files that match a specific size. E.g. -size +10M will find all files that are larger than 10MB, vice versa with -size -10M with the one that are smaller than 10MB.

-mtime: Files that have been modified within a specific time frame. E.g. -mtime -7 will find all files that have been modified within the last 7 days. +7 for more than 7 days.

-user: Files that are owned by a specific user. E.g. -user hacki

-exec: Executes a command on each file that is found. E.g. -exec ls -l {} \; will list the long format details of each file that is found.

Note: You could also use pipeline

*Note 2: EXTREMELY IMPORTANT, if you by and chance, use {} inside command substitution (e.g. -exec echo "$(dirname {})" \;), you must always remember that command substitution happens BEFORE the replacement of {}, so the command is running dirname {} instead of dirname <smt>, results in error.

-perm: Files that have been set permissions by User, Group or Others. e.g -perm /o+w means anyone with write permission, -perm /u-x means users without execute permission.

How to use multiple expressions

Using operators:

• ! (-not)
• -a (-and)
• -o (-or)
• ,

E.g.

find . -name "*.sh" -a -name "*.fish"

find . -path ./logs -prune -o -type f

*Note: the -not operator only applies to ONE option, use grouping \( and \) to encapsulate multiple option into one.

find . -maxdepth 1 \( -not -name ".config" -type d \) -o -name "*.sh" -type f: find all script files with extension "sh" and excludes .config directory.

find . -maxdepth 1 -not \( -name "*" -type d \) -o -name "*.sh" type f : find all script files with extension "sh" and all files that are not directory with any names (excludes all directories)

Best practices when using find command

Use -printf FORMAT option: by default, find command will prnit the name of each file that it finds

Use quotes "" to prevent the shell from interpreting any special character, usually Space.

Use -maxdepth option: search for a specific depth, avoid running too long.

Use -iname instead of -name option: case-insensitive search.

Use -prune to tell find to exclude a particular directory from the search.

E.g. to search all files in the current directory + its subdirectories, BUT, exclude the files in a directory named "logs"

find . -path ./logs -prune -o -type f -print

Here the -path option is used to specify the directory you want to exclude, and -prune tells find to exclude the directory from the search.

-prune option only works with directories. If you want exclude specific files from the search, use -not / ! operator with -name option