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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

execute a command in case of success or execute a command in case of failure

Do not clear the screen after viewing a file with less
From the manpage: $ man less -X or --no-init Disables sending the termcap initialization and deinitialization strings to the terminal. This is sometimes desirable if the deinitialization string does something unnecessary, like clearing the screen. Bonus: If you want to clear the screen after viewing a file this way that had sensitive information, hit or just type clear. Since is readily available, I don't know why less bothers to automatically clear. If you're viewing the file at all, chances are you want to see the output from it after you quit.

Socksify any program to avoid restrictive firwalls
Require: - tsocks (deb pkg) - A working SOCKS proxy. It's easy with ssh: $ ssh -N -D localhost:1080 your.home.pc -p 443 - tsocks configuration in your /etc/tsocks.conf (for the previous): server = 127.0.0.1 server_port = 1080

Search big files with long lines
This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error. Once you have run the above command (or put it in your .bashrc), files can be searched using: $ lgrep search-string /file/to/search

Making scripts runs on backgourd and logging output
Save all output to a log.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Use md5sum to check your music and movie files. Also use diff.
This is a beginning script. You can create a file with > filename. You can also use diff to compare output run at different times to verify no change in your files. I apologize in advance if this is too simple. For some it should be a start.

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" }

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


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