Commands by kniht (5)

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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

List open TCP/UDP ports

extract element of xml
poor man's xml parser :)

Show git branches by date - useful for showing active branches

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"

full path listing in /directory/path/* of javascript files.
file listing in /directory/path/* of specific files such as javascript(js) .

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Quick directory bookmarks
Set a bookmark as normal shell variable $ p=/cumbersome/path/to/project To go there $ to p This saves one "$" and is faster to type ;-) The variable is still useful as such: $ vim $p/ will expand the variable (at least in bash) and show a list of files to edit. If setting the bookmarks is too much typing you could add another function $ bm() { eval $1=$(pwd); } then bookmark the current directory with $ bm p

Rotate a video file by 90 degrees CW
Change video orientation in metadata only

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

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