Commands by brian (1)

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Remove all HTML tags from a file

find files ignoring .svn and its decendents

Number of files in a SVN Repository
This command will output the total number of files in a SVN Repository.

Resume scp of a big file
It can resume a failed secure copy ( usefull when you transfer big files like db dumps through vpn ) using rsync. It requires rsync installed in both hosts. rsync --partial --progress --rsh=ssh $file_source [email protected]$host:$destination_file local -> remote or rsync --partial --progress --rsh=ssh [email protected]$host:$remote_file $destination_file remote -> local

Non Numeric Check
use to execute a block of code only if $var is numeric

Summarize size of all files of given type in all subdirectories (in bytes)
This deals nicely with filenames containing special characters and can deal with more files than can fit on a commandline. It also avoids spawning du.

Generate random valid mac addresses
Ruby version. Also, a perl version: $perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'

Validating a file with checksum
Makes sure the contents of "myfile" are the same contents that the author intended given the author's md5 hash of that file ("c84fa6b830e38ee8a551df61172d53d7").

Grab IP address on machine with multiple interfaces
Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

PRINT LINE the width of screen or specified using any char including Colors, Escapes and metachars
One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol. This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings). If you do use terminal escapes this will reset to default. $ tput sgr0 For implementation ideas, check my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html


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