Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)
rename file name with fixed length nomeric format pattern Show Sample Output
The difference between the original version provided and this one is that this one works rather than outputting a wget error
Based on the MrMerry one, just add some visuals and sort directory and files
Run this as root, it will be helpful to quickly get information about the loaded kernel modules. Show Sample Output
Works with files containing spaces and for very large directories.
I like this better than some of the alternatives using -exec, because if I want to change the string, it's right there at the end of the command line. That means less editing effort and more time to drink coffee. Show Sample Output
for when a program is hogging the sound output. finds, and kills. add -9 to the end for wedged processes. add in 'grep ^program' after lsof to filter. Show Sample Output
unset PROMPT_COMMAND to disable. Show Sample Output
If you want to pull all of the files from a tree that has mixed files and directories containing files, this will link them all into a single directory. Beware of filesystem files-per-directory limits.
For instance:
find . -type f -name '*.wav' -print0 |xargs -0 -P 3 -n 1 flac -V8
will encode all .wav files into FLAC in parallel.
Explanation of xargs flags:
-P [max-procs]: Max number of invocations to run at once. Set to 0 to run all at once [potentially dangerous re: excessive RAM usage].
-n [max-args]: Max number of arguments from the list to send to each invocation.
-0: Stdin is a null-terminated list.
I use xargs to build parallel-processing frameworks into my scripts like the one here: http://pastebin.com/1GvcifYa
Tells you everything you could ever want to know about all files and subdirectories. Great for package creators. Totally secure too.
On my Slackware box, this gets set upon login:
LS_OPTIONS='-F -b -T 0 --color=auto'
and
alias ls='/bin/ls $LS_OPTIONS'
which works great.
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Can be used for other commands as well, replace rm with ls. It is easy to make this shorter but if the filenames involved have spaces, you will need to do use find's "-print0" option in conjunction with xargs's "-0" option. Otherwise the shell that xargs uses to execute the "rm" command line will treat the space as a token separator, thereby treating the name as two (or more) names. Show Sample Output
By time thumbnail images in ~/thumbnails take up too much space, this command will help deleting old ones. Find options explained: -type f : find files only, not directories -atime +30 : last accessed more than 30 days ago
Lists the local files that are not present in the remote repository (lines beginning with ?) and add them. Show Sample Output
In the example, uid 0 is root. foo:foo are the user:group you want to make owner and group. '.' is the "current directory and below." -print0 and -0 indicate that filenames and directories "are terminated by a null character instead of by whitespace."
use the locate command to find files on the system and verify they exist (-e) then display each one in full details. Show Sample Output
A little bit smaller, faster and should handle files with special characters in the name.
Liked command 4077 so I improved it, by doing all text manipulation with sed. "Run this as root, it will be helpful to quickly get information about the loaded kernel modules." THX mohan43u Show Sample Output
There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100.
OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 ))
This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript).
An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command.
find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p'
I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this:
cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}'
I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this.
cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}'
If you were building a process-killer (very common for cheap hosting) this would also be handy.
Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.
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Finds all C++, Python, SWIG files in your present directory (uses "*" rather than "." to exclude invisibles) and counts how many lines are in them. Returns only the last line (the total). Show Sample Output
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