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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.
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It is helpful to know the current limits placed on your account, and using this shortcut is a quick way to figuring out which values to change for optimization or security.
alias ulimith="command ulimit -a|sed 's/^.*\([a-z]\))\(.*\)$/-\1\2/;s/^/ulimit /'|tr '\n' ' ';echo"
Here's the result of this command:
ulimit -c 0 -d unlimited -e 0 -f unlimited -i 155648 -l 32 -m unlimited -n 8192 -p 8 -q 819200 -r 0 -s 10240 -t unlimited -u unlimited -v unlimited -x unlimited
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 155648
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 8192
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) unlimited
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
This is a minimalistic version of the ubiquitious Google definition screen scraper. This version was designed not only to run fast, but to work using BusyBox. BusyBox is a collection of basic Unix tools that have been compiled into a single binary to save space on tiny installations of Unix. For example, although my phone doesn't have perl or the GNU utilities, it does have BusyBox's stripped down versions of wget, tr, and sed. It turns out that those tools suffice for many tasks.
Known Bugs: This script does not handle HTML entities at all. I don't think there's an easy way to do that within BusyBox, but I'd love to see it if someone could do it. Also, this script can only define a single word, not phrases. (Well, you could if you typed in %20, but that'd be gross.) Lastly, this script does not show the URL where definitions were found. Given the randomness of the Net, that last bit of information is often key.
Use if you have pictures all over the place and you want to copy them to a central location
Find jpg files
translate all file names to lowercase
backup existing, don't overwrite, preserve mode ownership and timestamps
copy to a central location
This is similar to how you would generate a file with all zeros
dd if=/dev/zero of=allzeros bs=1024 count=2k
Transforms a file to all uppercase.
Also searches for aliases and shell builtins
Searches in order of the directories of $PATH. Stops after finding the entry; looks for only that fileName. Works in Bourne, Korn, Bash and Z shells.
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command
Save the script as: sort_file
Usage: sort_file < sort_me.csv > out_file.csv
This script was originally posted by Admiral Beotch in LinuxQuestions.org on the Linux-Software forum.
I modified this script to make it more portable.
Puts words on new lines, removing additional newlines.
Helpful when we want to do mass file renaming(especially mp3s).
curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).
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.
This command might not be useful for most of us, I just wanted to share it to show power of command line.
Download simple text version of novel David Copperfield from Poject Gutenberg and then generate a single column of words after which occurences of each word is counted by sort | uniq -c combination.
This command removes numbers and single characters from count. I'm sure you can write a shorter version.
This will, for an application that has already been removed but had its configuration left behind, purge that configuration from the system. To test it out first, you can remove the last -y, and it will show you what it will purge without actually doing it. I mean it never hurts to check first, "just in case." ;)