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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
instead of printing the whole line, print just the capture matched, but with the "cut" pipe :( I'm so sad with grep.
When you need a quick ref guide while troubleshooting Apache|NGINX error|access logs.
Shows a sigclass 0x20 (Key revocation) signature packet on a key, including all subpackets. Subpacket 2 is the date of revocation, subpacket 26 the relevant policy, subpacket 29 the reason of revocation (cf. http://rfc.askapache.com/rfc4880/rfc4880.html#section-220.127.116.11 ) and subpacket 16 the issuer of the revocation certificate (usually should be the same as the revoked key).