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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):
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This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files.
The combination of print0 and files0-from options makes the whole command simple and efficient.
Makes any files in the current directory (and any sub-directories) group-readable.
Using the "! -perm /g=r" limits the number of files to only those that do not already have this property
Using "+" on the end of the -exec body tells find to build the entire command by appending all matching files before execution, so invokes chmod once only, not once per file.
Obviously, you can replace 'man' command with any command in this command line to do useful things. I just want to mention that there is a way to list all the commands which you can execute directly without giving fullpath.
Normally all important commands will be placed in your PATH directories. This commandline uses that variable to get commands. Works in Ubuntu, will work in all 'manpage' configured *nix systems.
"find . -type d -print0 | xargs -0 chmod 755"
With this command you can get a previous or future date or time. Where can you use this? How about finding all files modified or created in the last 5 mins?
touch -t `echo $(date -d "5 minute ago" "+%G%m%d%H%M.%S")` me && find . -type f -newer me
List all directories created since last week?
touch -t `echo $(date -d "1 week ago" "+%G%m%d%H%M.%S")` me && find . -type d -cnewer me
I'm sure you can think of more ways to use it. Requires coreutils package.
unzips all zip files in any subdirectory under the current directory. The zip files are unzipped in their respective subdirs
In the example, uid 0 is root. foo:foo are the user:group you want to make owner and group. '.' is the "current directory and below." -print0 and -0 indicate that filenames and directories "are terminated by a null character instead of by whitespace."
This uses Bash's "process substitution" feature to compare (using diff) the output of two different process pipelines.
The "find" command can be annoying when used inside of a Subversion (or CVS) working directory. Obviously, you can combine this with other predicates and commands to create a more elaborate pipeline:
find /var/svn -type f -not \( -name .svn -prune \) -print0 | xargs -0 md5sum
Note: You can use my "dont-go-there.sh" script to wrap the "find" command and do this automatically at http://forwardlateral.com/blog/2006/02/27/dont-go-there/
Deletes empty directories and prints an error if directory is not empty.
find largest file in /var
I have a bash alias for this command line and find it useful for searching C code for error messages.
The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching.
This find command find all .c and .h files
Change your wallpaper every thirty minutes (or however long you like, I suppose) to a randomly selected image in a directory and subdirectories. Bear in mind this is not safe to use if anyone else has write access to your image directory.
Clone linux installation.
Copy every file from current directory to destination preserving modification time.
Have a grudge against someone on your network? Do a "find -writable" in their directory and see what you can vandalize! But seriously, this is really useful to check the files in your own home directory to make sure they can't inadvertently be changed by someone else's wayward script.
By time thumbnail images in ~/thumbnails take up too much space, this command will help deleting old ones.
Find options explained:
-type f : find files only, not directories
-atime +30 : last accessed more than 30 days ago
This is useful if you have a collection of files in folders (for example, a bunch of .zip files that are contained in folders) and you want to move them all to a common folder.