Commands tagged xargs

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.

xargs deals badly with special characters (such as space, ' and "). In this case if you have a file called '12" record'.

Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.

Both solutions work bad if the number of files is more than the allowed line length of the shell.

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.

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.

A bit shorter and parallelized. Depending on the speed of your cpu and your disk this may run faster.

Parallel is from https://savannah.nongnu.org/projects/parallel/

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.

Use if you have pictures all over the place and you want to copy them to a central location

Synopsis:

Find jpg files

translate all file names to lowercase

backup existing, don't overwrite, preserve mode ownership and timestamps

copy to a central location

I modify 4077 and marssi commandline to simplify it and skip an error when parsing the first line of lsmod (4077). Also, it's more concise and small now. I skip using xargs ( not required here ). This is only for GNU sed.

For thoses without GNU sed, use that :

Liked command 4077 so I improved it, by doing all text manipulation with sed.

"Run this as root, it will be helpful to quickly get information about the loaded kernel modules." THX mohan43u

Run this as root, it will be helpful to quickly get information about the loaded kernel modules.

With this form you dont need to cut out target directory using grep/sed/etc.

Nice command to create a list, you can create too with for command, but this is so faster.

I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server.

So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg.

Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting.

Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl?

Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links....

Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

A little bit smaller, faster and should handle files with special characters in the name.

Based on the MrMerry one, just add some visuals and sort directory and files

use the locate command to find files on the system and verify they exist (-e) then display each one in full details.

xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

By putting the "-not \( -name .svn -prune \)" in the very front of the "find" command, you eliminate the .svn directories in your find command itself. No need to grep them out.

You can even create an alias for this command:

Now you can do things like

will purge:

only installed apps: /^ii/!d

avoiding current kernel stuff: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

using app names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

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."