Commands by unixmonkey20182 (1)

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vi a remote file
notice the double slash

Insert commas to make reading numbers easier in the output of ls
This modifies the output of ls so that the file size has commas every three digits. It makes room for the commas by destructively eating any characters to the left of the size, which is probably okay since that's just the "group".   Note that I did not write this, I merely cleaned it up and shortened it with extended regular expressions. The original shell script, entitled "sl", came with this description:    : '  : For tired eyes (sigh), do an ls -lF plus whatever other flags you give  : but expand the file size with commas every 3 digits. Really helps me  : distinguish megabytes from hundreds of kbytes...  :  : Corey Satten, [email protected], 11/8/89  : '   Of course, some may suggest that fancy new "human friendly" options, like "ls -Shrl", have made Corey's script obsolete. They are probably right. Yet, at times, still I find it handy. The new-fangled "human-readable" numbers can be annoying when I have to glance at the letter at the end to figure out what order of magnitude is even being talked about. (There's a big difference between 386M and 386P!). But with this nifty script, the number itself acts like a histogram, a quick visual indicator of "bigness" for tired eyes. :-)

Recursively remove directory with many files quickly
rsync'ing an empty directory over a directory to be deleted recursively is much faster than using rm -rf, for various reasons. Relevant only for directories with really a lot of files.

Find unused IPs on a given subnet
Somewhat shorter version.

Get a list of IP Addresses that have failed to login via SSH
This command shows a sorted list of the IP addresses from which there have been authentication errors via SSH (possible script kiddies trying to gain access to your server), it eliminates duplicates so it's easier to read, but you can remove the "uniq" command at the end, or even do a "uniq -c" to have a count of how many times each IP address shows in the log (the path to the log may vary from system to system)

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

Exclude svn directories with grep
exclude-dir option requires grep 2.5.3

Remove newlines from output
?Cat and grep? You can use only grep ("grep \. filename"). Better option is awk.

Direct auto-complete in bash
Direct auto-complete in bash

convert wav files to ogg
cd to the folder containing the wav files and convert them all to ogg format. in my sample output i use the -a and -l flags to set the author and album title. to get the oggenc program in ubuntu linux run: sudo apt-get install oggenc


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