Commands by sammcj (6)

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Random quote from Borat -- no html parsing
Turns out smacie.com has a text file containing every single one of the borat quotes, each one on a newline. This makes it very convenient, as this can be done without any sed-parsing, and uses less bandwitdth! Note that borate quotes are quite offensive, much more so than "fortunes-off"!

Create sqlite db and store image
Creates a simple sqlite db (img.db) inserts /tmp/Q.jpg on base64 an recorvers it as /tmp/W.jpg

Top 10 requestors by IP address from Apache/NCSA Logs

tcpdump top 10 talkers
capture 2000 packets and print the top 10 talkers

Extract multiple tar files at once in zsh
tar doesn't support wildcard for unpacking (so you can't use tar -xf *.tar) and it's shorter and simpler than for i in *.tar;do tar -xf $i;done (or even 'for i in *.tar;tar -xf $i' in case of zsh) -i says tar not to stop after first file (EOF)

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.

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Go to directory or creat it and go to
For use in scripts this command is very usefull

sed /pat/!d without using sed (no RE; limited to shell patterns aka globbing)
POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.

Change a specific value in a path
Awk replaces the value of a specific field while retaining the field separator "/" .


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