Commands by syladmin (5)

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Check reverse DNS
The +short option should make dig less chatty.

modify a file in place with perl
changes THIS to THAT in all files matching fileglob* without using secondary files

Convert a script to one-liner
Opposite: Convert an one-liner to script: $ foo() { ; } ... $ typeset -f foo ... $ unset -f foo

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

Remove all unused kernels with apt-get
TIMTOWTDI

Perl One Liner to Generate a Random IP Address

Filter out all blank or commented (starting with #) lines

Recursive replace of directory and file names in the current directory.
This should work anywhere perl and grep is available. :P

Display the output of a command from the first line until the first instance of a regular expression.
If BREs can be used, this sed version will also get the job done.

Fix "broken" ID3 tags in the current directory and subdirectories
Some MP3s come with tags that don't work with all players. Also, some good tag editors like, EasyTAG output tags that don't work with all players. For example, EasyTAG saves the genre as a numeric field, which is not used correctly in Sansa MP3 players. This command corrects the ID3 tags in MP3 files using mid3iconv, which comes with mutagen. To install Mutagen on Fedora use "yum install python-mutagen"


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