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Work for me on CentOS, grep and print ip addresses of ssh bruteforce attempts
If you run this command on a VMWare Virtual Machine, it will return the string "VMware Virtual Platform". If you run it on a physical machine, it will return nothing. Useful for having a script determine if it's running on a VM or not. Of course, you must have dmidecode installed for this to work.
Try it this way in a script: ISVM=$(dmidecode | awk '/VMware Virtual Platform/ {print $3,$4,$5}')
Then test if $ISVM has text in it, or is blank.
You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds.
Someone better at awk could probably reduce this down a lot.
inputfile.txt is a space-separated textfile, 1st column contains the items (id) I want to put into my SQL statement.
39 = charactercode for single tick '
1 = first column
If inputfile.txt is a CSV-file separated by "," use FS= to define your own field-separator:
awk 'BEGIN {FS=","; }{printf "select * from table where id = %c%s%c;\n",39,$1,39; }' inputfile.txt
worked on ubuntu 9.04 and cygwin with MS netstat
After executing this, click on a window you want to track X Window events in.
Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo"
Show apps that use internet connection at the moment.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes.
This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO")
This corrects duplicate output from the previous command.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.
Has anyone an idea why the uniq doesn't work propperly here (see sample output)?
I sometimes (due to mismanagement!) end up with files in a git repo which have had their modes changed, but not their content. This one-liner lets me revert the mode changes, while leaving changed-content files be, so I can commit just the actual changes made.
I have a directory containing log files. This command delete all but the 5 latest logs. Here is how it works:
* The ls -t command list all files with the latest ones at the top
* The awk's expression means: for those lines greater than 5, delete.
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.
This is an on-line algorithm for calculating the mean value for numbers in a column. Also known as "running average" or "moving average".
This command displays a list of lines that are longer than 72 characters. I use this command to identify those lines in my scripts and cut them short the way I like it.
Connect to a machine running ssh using mac address by using the "arp" command
Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts.
This is really fast :)
time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
204753
real 0m0.191s
user 0m0.068s
sys 0m0.116s
Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages.
For some reason sed gets stuck on OS X, so here's a Perl version for the Mac:
curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*<name>(.*)<\/name>.*$/$2 - $1/'
If you want to see the name of the last person, who added a message to the conversation, change the greediness of the operators like this:
curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*?<name>(.*?)<\/name>.*$/$2 - $1/'