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Get all URLs from webpage via Regular Expression
Get all URLs from website via Regular Expression... You must have lynx installed in your computer to execute the command. --> lynx --dump "" | egrep -o "" - Must substitute it for the website path that you want to extract the URLs - Regular Expression that you wanna filter the website

TCPDUMP & Save Capture to Remote Server w/ GZIP
NOTE: When opening the files you might need to strip the very top line with notepad++ as its a mistake header This is useful when the local machine where you need to do the packet capture with tcpdump doesn?t have enough room to save the file, where as your remote host does tcpdump -i eth0 -w - | ssh forge.remotehost.com -c arcfour,blowfish-cbc -C -p 50005 "cat - | gzip > /tmp/eth0.pcap.gz" Your @ PC1 doing a tcpdump of PC1s eth0 interface and its going to save the output @ PC2 who is called save.location.com to a file /tmp/eth0-to-me.pcap.gz again on PC2 More info @: http://www.kossboss.com/linuxtcpdump1

Remove trailing space in vi

benchmark web server with apache benchmarking tool
-n 9000 : Number of requests to perform for the benchmarking session -c 900 : Number of multiple requests to perform at a time

firefox: how many eat?

View any already in progress copy command in detail
If you spot a dubious looking cp command running you can use this command to view what is being copied and to where. 1234 is the PID of the cp command being passed to the lsof utility. 3r.*REG will display the file/directory that is being read/copied. 4w.*REG will display the destination it is being written to.

strip config files of comments
some configuration files, particularly those installed by default as part of a package, have tons of comment lines, to help you know what's possible to configure, and what it means. That's nice, but sometimes you just want to see what specifically what _has_ been configured. That's when I use the above snippet, which I save as a bash alias 'nocom' (for 'no comments'). Apache default config files are perfect examples of when/why this script is handy.

Generate hash( of some types) from string
No need to install yet another program when openssl is already installed. :-)

Search for a string inside all files in the current directory
options: -n line nbrs, -i ignore case, -s no "doesn't exist", -I ignore binary args: * for all files of current dir (not hidden), .[!.]* for all hidden files I don't include by default the -R (recursive) option, which is not always useful. You add it by hand when needed.

skip broken piece of a loop but not exit the loop entirely
useful for loops like for i in $(cat list_of_servers); do ssh -q $i hostname; done if there is an unreachable server, you can just press ctrl + \ to skip that server and continue on with the loop


Stay in the loop…

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