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Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
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Fast and easy way to find all established tcp connections without using the netstat command.
Go to "https://twitter.com/search/realtime?q=%23TeamFollowBack&src=hash" and then copy al the text on the page. If you scroll down the page will be bigger. Then put al the text in a text file called twit.txt
If you follow the user there is a high probability the users give you follow back.
To follow all the users you can use an iMacros script.
This command produces no output, but its exit status is 0 ("true") if $file is text, non-0 ("false") if $file is binary (or is not accessible).
-q suppresses all the output of grep
-I is the trick: if a binary file is found, it is considered a non-match
-m 1: limit "output" to first match (speed up for big files)
.: the match string, "." stands for any character
Usage: e.g. run editor only on text files
grep -qIm 1 . $file && vi $file
calculate how many different lines between two files
Reason can be: taken, available, contains_banned_word
I use these command to validate twitter accounts, we can use a "for a in $(cat list.txt)" to validate a complete list of twitter accounts.
Open Port Check
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients:
tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'
Get the longest match of file extension (Ex. For 'foo.tar.gz', you get '.tar.gz' instead of '.gz')
Returns the version of the kernel module specified as "MODULENAME", when available.
`pwd` returns the current path
`grep -o` prints each slash on new line
perl generates the paths sequence: './.', './../.', ...
`readlink` canonicalizes paths (it makes the things more transparent)
`xargs -tn1` applies chmod for each of them. Each command applied is getting printed to STDERR.
In these command i use lynx to get the top trend topic of Mexico, if you replace Mexico with other country, you will get the #1 Trending topic
Replace "user/sbin/sshd" with the file you would like to check. If you are doing this due to intrusion, you obviously would want to check size, last modification date and md5 of the md5sum application itself. Also, note that "/var/lib/dpkg/info/*.md5sums" files might have been tampered with themselves. Neither to say, this is a useful command.
Created to deal with an overzealous batch rename on our server that renamed all files to .jpg files.
Long listing alternative
Get the amount of physical memory in an HP-UX v11 OS when following are NOT available:
- root account
- no privileges in /proc
- no privileges in /dev/mem