find' is one of the '''on-board power tools''' that you should know well. It it '''the one' tools that operates on hierarchical filesystem tree structure'''.
Only in some modern Unix systems there are other tools that have a recursive Switch (z.B. grep -R) who can directly operate on filesystem hierarchies. However find has many tricks in its sleeve to that will allow you to to things that other commands cannot.

find Options

    long listing 
    everything is taken literally so files can contain quotes and spaces. Strings have aree \0 terminated 
    ask before exec cmd 
    ask before exec cmd 
 -perm 75  
    exactly rwxr-xr-x 
 -perm -002  
    general readable files (all bits set) 
 -perm +1000 
    any of the bits set 
 - !  
    out of f, d 
 -size +100  
    size greater 100k 
    access for n days 
    modify for n days 
    group that is not mentioned in group file 
 -inum number TRUE if file has inode number. 

Examples - Tips and Tricks

Protect Web-files

Protect Web-files and make them global readable so even the owner can not add them. 444 is a octal numerical representation of the file permissions (-r--r--r--).
 find . -type f | xargs chmod 444

Delete a file wit special characters in the filename

 6423022 -rw-r--r--   1 ahaack  staff     0 11 Nov 10:08 ??

6423022 is the inode number of the strange file shown as "??"

 find . -inum 6423022 -ok rm "{}" \;
 "rm ./??"? y

Delete all .cache files in the html director tree

 find . -name ".cache" | xargs rm

Create an RCS directory in every sub directory

Create an RCS directory in every sub directory , except where one already exists The trick here is to prevent create a subdirectory where a RCS directory already exist (e.g. RCS/RCS/RCS ).
find . -type d -a ! -name RCS -exec mkdir {}/RCS \;

Search for "localhost" in all php files

On Linux the command can handle files that contain spaces.
 find . -name "*.php" -print0 | xargs -0 grep "localhost"

Status: Published Date: 2014-08-28 00:59:37 +0200 (Thu, 28 Aug 2014) Revision: 20

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