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While `echo rm * | batch` might seem to work, it might still raise the load of the system since `rm` will be _started_ when the load is low, but run for a long time. My proposed command executes a new `rm` execution once every minute when the load is small.
Obviously, load could also be lower using `ionice`, but I still think this is a useful example for sequential batch jobs.
This can be used to delete or archive old mails. In fact, for archiving its a bit different, you need to archive mails with any tools (e.g archivemail), and then deleting (if you want!).
Here we use -path ".*/cur/*" to avoid files limit in bash globbing and to search in any inbox (e.g .mymail .spam .whatever).
! -newermt "1 week ago" can be read: All files which is older than "1 week ago", adapt it in consequence.
This command is recursive and will delete in all directories in ".". It will find and delete all files not specified with ! -name "pattern". In this case it's file extensions. -type f means it will only find files and not directories. Finally the -delete flag ask find to delete what it matches. You can test the command by running it first without delete and it will list the files it will delete when you run it.
Maybe you want first check which files will be deleted:
find $HOME -name '*.sol' -exec echo rm {} \;
grep searches through a file and prints out all the lines that match some pattern. Here, the pattern is some string that is known to be in the deleted file. The more specific this string can be, the better. The file being searched by grep (/dev/sda1) is the partition of the hard drive the deleted file used to reside in. The ?-a? flag tells grep to treat the hard drive partition, which is actually a binary file, as text. Since recovering the entire file would be nice instead of just the lines that are already known, context control is used. The flags ?-B 25 -A 100? tell grep to print out 25 lines before a match and 100 lines after a match. Be conservative with estimates on these numbers to ensure the entire file is included (when in doubt, guess bigger numbers). Excess data is easy to trim out of results, but if you find yourself with a truncated or incomplete file, you need to do this all over again. Finally, the ?> results.txt? instructs the computer to store the output of grep in a file called results.txt.
As a user, deletes all your posts from a MyBB board (provided you have the search page listings of all your posts saved into the same directory this command is run from). Full command:
for i in *; do cat $i | grep pid | sed -e 's/;/\ /g' -e 's/#/\ /g' -e 's/pid=/\ /g' | awk -F ' ' '{print $2}' >> posts.txt; done; for c in `cat posts.txt`; do curl --cookie name= --data-urlencode name=my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c --user-agent Firefox\ 3.5 --url http://url/editpost.php?my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c; sleep 2s; done; echo
This will search all directories and ignore the CVS ones. Then it will search all files in the resulting directories and act on them.
This will find all files under the path "." which are older than 10 days, and delete them. If you wish to use the "rm" command instead, replace "-delete" with "-exec rm [options] {} \;"
Instead, install apt-get install secure-delete and you can use:
-- srm to delete file and directory on hard disk
-- smem to delete file in RAM
-- sfill to delete "free space" on hard disk
-- sswap to delete all data from swap
xargs deals badly with special characters (such as space, ' and "). To see the problem try this:
touch important_file
touch 'not important_file'
ls not* | xargs rm
Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.
ls -Q will show the filenames in quotes. xargs -p rm will print all the filenames piped from ls -Q and ask for confirmation before deleting the files.
without the -Q switch, if we have spaces in names, then the files won't be deleted.
This command is useful if you accidentally untar or unzip an archive in a directory and you want to automatically remove the files. Just untar the files again in a subdirectory and then run the above command e.g.
for file in ~/Desktop/temp/*; do rm ~/Desktop/`basename $file`; done
This command will delete files i a given path (/dir_name) , which older than given time in days (-mtime +5 will delete files older than five days.