Commands by kkapron (1)

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c_rehash replacement
When you don't have c_rehash handy. Really simple - if you have a .pem file that doesn't really contain a x509 cert (let's say, newreq.pem), it will create a link, simply called '.0', pointing to that file.

Watch the progress of 'dd'
The 'dd' command doesn't provide a progress when writing data. So, sending the "USR1" signal to the process will spit out its progress as it writes data. This command is superior to others on the site, as it doesn't require you to previously know the PID of the dd command.

List all duplicate directories
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical. if in doubt apply: $ diff -rq path_to_dir1 path_to_dir2 AWK function taken from here: http://stackoverflow.com/questions/2912224/find-duplicates-lines-based-on-some-delimited-fileds-on-line

Fire CMD every time FILE (or directory) is updated (on *BSD)

multiline data block parse and CSV data extraction with perl
extract data in multiline blocks of data with perl pattern matching loop

Download Apple movie trailers
Copy the link to an HD movie trailer in to this command. It's more eleganant if it's put in a to a script, taking the URL as input.

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Block all IP addresses and domains that have attempted brute force SSH login to computer
Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.

Get IP from hostname
Get the IP of a hostname.


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