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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

move up through directories faster (set in your /etc/profile or .bash_profile)
You can also remove the "&& pwd" if you don't want it to print out each directory as it moves up.

find previously entered commands
Searches bash-history in reverse order (last entered commands first). Pressing ctrl+r again shows the next matching entry.

Copy a MySQL Database to a new Server via SSH with one command
Dumps a MySQL database over a compressed SSH tunnel and uses it as input to mysql - i think that is the fastest and best way to migrate a DB to a new server!

View files opened by a program on startup and shutdown
Run this before you run a command in order to see what the command does as it starts. The -c flag is useful here as the PID is unknown before startup. All config files, libraries, logs, ports, etc used by the command as it starts up, (and shuts down) will be captured at 1s intervals and written to a file. Useful for debugging etc.

Analyze awk fields
translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)

Batch-Convert text file containing youtube links to mp3

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" }

Give any files that don't already have it group read permission under the current folder (recursive)
Makes any files in the current directory (and any sub-directories) group-readable. Using the "! -perm /g=r" limits the number of files to only those that do not already have this property Using "+" on the end of the -exec body tells find to build the entire command by appending all matching files before execution, so invokes chmod once only, not once per file.

Fire CMD every time FILE (or directory) is updated (on *BSD)


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