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Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via:
cp /proc/pid/fd/filehandle /new/file.txt
somewhat faster version to see the size of our directories. Size will be in Kilo Bytes. to view smallest first change '-k1nr' to '-k1n'.
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.
Useful if you have to put together multiple files into one and they are scattered across subdirectories. For example: You need to combine all .sql files into one .sql file that would be sent to DBAs as a batch script.
You do get a warning if you create a file by the same extension as the ones your searching for.
find . -type f -name *.sql -exec cat {} > BatchFile.txt \;
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.
Here the pattern is '*.jar', you could pass in any pattern.
Another, maybe nicer way to do this is
You could replace sed with tr
"find . -type d -print0 | xargs -0 chmod 755"
thanks masterofdisaster
This one-liner will the *delete* without any further confirmation all 100% duplicates but one based on their md5 hash in the current directory tree (i.e including files in its subdirectories).
Good for cleaning up collections of mp3 files or pictures of your dog|cat|kids|wife being present in gazillion incarnations on hd.
md5sum can be substituted with sha1sum without problems.
The actual filename is not taken into account-just the hash is used.
Whatever sort thinks is the first filename is kept.
It is assumed that the filename does not contain 0x00.
As per the good suggestion in the first comment, this one does a hard link instead:
find . -xdev -type f -print0 | xargs -0 md5sum | sort | perl -ne 'chomp; $ph=$h; ($h,$f)=split(/\s+/,$_,2); if ($h ne $ph) { $k = $f; } else { unlink($f); link($k, $f); }'
If you don't want to delete them, but just want to list them, do
find -L /path -type l
If you want to delete them with confirmation first, do
find -L /path -type l -exec rm -i {} +
Using the -L flag follows symlinks, so the -type l test only returns true if the link can't be followed, or is a symlink to another broken symlink.
added alias in ~/.bashrc
alias lf='find ./* -ctime -1 | xargs ls -ltr --color'
Finds all corrupted jpeg files in current directory and its subdirectories. Displays the error or warning found.
The jpeginfo is part of the jpeginfo package in debian.
Should you wish to only get corrupted filenames, use cut to extract them :
find ./ -name *jpg -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR" | cut -d " " -f 1
Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option.
This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files.
Putting one alias in .profile will be more useful.
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/