Commands by drewbenn (2)

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Go to parent directory of filename edited in last command
Uses the last argument of the last executed command, and gets the directory name from it. Use $!:t for the filename alone, without the dirname.

Execute a sudo command remotely, without displaying the password
The ssh command alone will execute the sudo command remotely, but the password will be visible in the terminal as you type it. The two stty commands disable the terminal from echoing the password back to you, which makes the remote sudo act as it does locally.

Skip over .svn directories when using the "find" command.
The "find" command can be annoying when used inside of a Subversion (or CVS) working directory. Obviously, you can combine this with other predicates and commands to create a more elaborate pipeline: $ find /var/svn -type f -not \( -name .svn -prune \) -print0 | xargs -0 md5sum Note: You can use my "dont-go-there.sh" script to wrap the "find" command and do this automatically at http://forwardlateral.com/blog/2006/02/27/dont-go-there/

Convert a Nero Image File to ISO
This line removes the 300k header from a Nero image file converting it to ISO format

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

Fake system time before running a command
Fake system time before running any command.

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

convert from decimal to hexadecimal
Use the standard calculator bc to convert decimals to hex

Multiple variable assignments from command output in BASH
It's quite easy to capture the output of a command and assign it in a shell's variable: $ day=$(date +%d) $ month=$(date +%m) But, what if we want to perform the same task with just one program invocation? Here comes the power of eval! date(1) outputs a string like "day=29; month=07; year=11" (notice the semicolons I added on purpose at date's custom output) which is a legal shell line. This like is then parsed and executed by the shell once again with the help of eval. Just setting 3 variables! Inspired by LinuxJournal's column "Dave Taylor's Work the Shell".

List all installed PERL modules by CPAN
This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.


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