Commands by hakamadare (1)

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Every Nth line position # (SED)
sed extract every nth line. Generic is: $ sed -n 'STARTPOSITION,${p;n;*LINE}' foo where n;*LINE = how many lines. thus p;n;n; is "for every 3 lines" and p;n;n;n;n; is "for every 5 lines"

BASH: Print shell variable into AWK
Alternatively: export MyVAR=84; awk '{ print ENVIRON["MyVAR"] }'

Create higher quality gif from videos
I had to compress it a bit to meet the 255 limit. See sample for full command (274) usage: ffgif foo.ext Supports 3 arguments (optional) ffgif filename seek_time time_duration scale ffgif foo 10 5 320 will seek 10 seconds in, convert for 5 seconds at a 320 scale. Default will convert whole video to gif at 320 scale. Inspiration - http://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality/556031#556031

HTTP Get of a web page via proxy server with login credentials
If you are behind a proxy server and have to authenticate with proxy server to browser web pages then you have to pass proxy server address and its port number along with user credentials to curl to got GET the page using curl. Example : "curl -U srikanth -x 167.85.103.70:8080 http://www.yahoo.com". In case you don't specify the password (as in the above example), curl will prompt to enter the password at the command line.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Ping xxx.xxx.xxx.xxx ip 100000 times with size 1024bytes

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"

Launch firefox on a remote linux server
Actually 'firefox' is a script that then launches the 'firefox-bin' executable. You need to specify the 'no-remote' option in order to launch remote firefox instead of your local one (this drove me crazy time ago)

Use vi commands to edit your command lines
If you spend all day editing in vi then switching your fingers to Emacs mode just for the command line can be difficult. Use set -o vi in your bash shell and enjoy the power of a real editor.

Find the package that installed a command


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