On Linux we can perform file searching in many ways. For Instance, from Nautilus (the Gnome’s file manager) we can search on the current directory for all mp3′s files using this expression ‘*.mp3′. But if we need to do more complicated searches, for example all mp3′s files greater than 5 MB, Nautilus is not the answer. In this cases we have to use a versatile and powerful command: find.
Using find
Find lets us make file searching on the system according to an expression. The basic syntax is:
find path expression
Where expression is made up of options (change general behavior) , tests (to return true or false) and actions (for processing the files found)
Lets see some options, tests and actions…
Options
| -maxdepth | n | Descend at most levels |
| -mount | Don’t descend directories on other filesystems |
Tests
| n | for exactly n | |
| +n | for greater than n | |
| -n | For less than n | |
| -amin | n | File was last accessed n minutes ago |
| -anewer | file | File was last accessed more recently than file was modified |
| -atime | n | File was last accessed n*24 hours ago |
| -cmin | n | File’s status was last changed n minutes ago |
| -cnewer | file | File’s status was last changed more recently than file was modified. |
| -ctime | n | File’s status was last changed n*24 hours ago |
| -mmin | n | File’s data was last modified n minutes ago |
| -newer | file | File was modified more recently than file |
| -mtime | n | File’s data was last modified n*24 hours ago |
| -empty | File is empty and is either a regular file or a directory | |
| -executables | Matches files which are executable and directories which are searchable | |
| -readable | Matches files which are readable | |
| -fstype | type | File is on a filesystem of type type |
| -uid | n | File’s numeric user ID is n |
| -user | user_name | File is owned by user user_name |
| -gid | n | File’s numeric group ID is n |
| -group | group_name | File belongs to group group_name |
| -name | pattern | Base of file name (the path with the leading directories removed) matches shell pattern pattern |
| -nogroup | No group corresponds to file’s numeric group ID | |
| -nouser | No user corresponds to file’s numeric user ID | |
| -perm | mode | File’s permission bits are exactly mode (octal or symbolic) |
| -perm | -mode | All of the permission bits mode are set for the file |
| -perm | /mode | Any of the permission bits mode are set for the file |
| -size | n[cwbkMG] | File uses n units of space |
| -type | c | File is of type c (block, character, directory, symbolic link, regular file, etc. |
Actions
| -delete | Delete files; true if removal succeeded | |
| -exec | comando ; | Execute command; true if 0 status is returned |
| -exec | comando ‘{}’ \; | This variant of the -exec action runs the specified command on the selected files, but the command line is built by appending each selected file name at the end |
Examples
| find /home -name ‘*.bash*’ | Any file which name contains .bash in its name, on the /home directory |
| find $HOME -mtime 0 | Files on user’s home directory modified less than 24 hours ago |
| find -perm 644 | Search for files which have read and write permission for their owner, and group, but which other users can read but not write to. Files which meet these criteria but have other permissions bits set (for example if someone can execute the file) will not be matched |
| find -perm -644 | Search for files which have read and write permission for their owner and group, and which other users can read, without regard to the presence of any extra permission bits (for example the executable bit). This will match a file which has mode 0777, for example. |
| find -perm /222 | Search for files which are writable by somebody (their owner, or their group, or anybody else) |
| find -perm /u=w | Same than above example |
| find /home -nouser -exec rm -r ‘{ }’ \; | Delete files on /home directory that belongs to nobody |
| find /home -size +1G | Search for files greater than a 1 GB on /home |
| find / -size +1G -user lgallard | Search for files greater than a 1 GB on /home which belongs to lgallard |
References
- http://en.wikipedia.org/wiki/Find
- http://www.gnome.org/~newren/tutorials/developing-with-gnome/html/re02.html
Planeta Linux
#1 by Luis Gallardo on 27/03/2010 - 7:24 am
@antonio Buscar todos los archivos en el directorio actual, sin importar que tenga mayúsculas o minúsculas (un poco sin sentido, ya que usas el comodín *)
#2 by antonio on 27/03/2010 - 5:41 am
¿que hace el comando find . iname *?