Commands using awk (1,418)

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port scan using parallel
It takes over 5 seconds to scan a single port on a single host using nmap $ time (nmap -p 80 192.168.1.1 &> /dev/null) real 0m5.109s user 0m0.102s sys 0m0.004s It took netcat about 2.5 minutes to scan port 80 on the class C $ time (for NUM in {1..255} ; do nc -w 1 -z -v 192.168.1.${NUM} 80 ; done &> /dev/null) real 2m28.651s user 0m0.136s sys 0m0.341s Using parallel, I am able to scan port 80 on the entire class C in under 2 seconds $ time (seq 1 255 | parallel -j255 'nc -w 1 -z -v 192.168.1.{} 80' &> /dev/null) real 0m1.957s user 0m0.457s sys 0m0.994s

Capture video of a linux desktop
This will grab the image from desktop, starting with the upper-left corner at x=100, y=200 with a width and height of 1024?768.

Extract audio track from a video file using mencoder
Extracts an MP3 encoded audio stream from an input video file.

calulate established tcp connection of local machine
If you want prepend/append text just wrap in echo: $echo Connected: `netstat -an|grep -ci "tcp.*established"`

Adjust all EXIF timestamps in .mov by +1 hour
works for Powershot SD780 IS

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Converts uppercase chars in a string to lowercase

display ip address
add this alias in .bashrc to fast check the ip address of your modem router alias myip="curl -s http://myip.dk | grep '' | sed -e 's/]*>//g'"

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Search and replace text in all php files with ruby
Search for the string "search" and replace it with the string "replace", on all files with the extension php in the curret folder. Do also a backup of each file with the extension "bkp".


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