Commands using tail (292)

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Fetch the Gateway Ip Address
This is to fetch the Gateway Ip Address of a machine. Use the below format to put the value in a variable if you wish to find the gateway ip in a script $GATEWAY=$(netstat -nr | awk 'BEGIN {while ($3!="0.0.0.0") getline; print $2}')

Revert all modified files in an SVN repo

Ctrl+S Ctrl+Q terminal output lock and unlock
These are simple shortcuts to pause and continue terminal output, works in most terminals and screen multiplexers like screen. You can use it to catch something if things change too fast, and scroll with Shift + PgUp PgDown. On linux console ScrollLock can also be used.

Insert a colon between every two digits
I sometimes have large files of MAC addresses stored in a file, some databases need the information stored with the semicolon (makes for easier programming a device) others don't. I have a barcode to text file scanner which usually butchers MAC addresses so this was the fix> I initially did this in awk ;) awk '{for(i=10;i>=2;i-=2)$0=substr($0,1,i)":"substr($0,i+1);print}' mac_address_list

Find the package that installed a command

Replace all in last 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

Number of CPU's in a system
/proc/cpuinfo contains information about the CPU. Search for "processor" in the /proc/cpuinfo file wc -l, counts the number of lines.

geoip information
Not my script. Belongs to mathewbauer. Used without his permission. This script gives a single line as shown in the sample output. NOTE: I have blanked out the IP address for obvious security reasons. But you will get whatever is your IP if you run the script. Tested working in bash.

Recursively search and replace old with new string, inside every instance of filename.ext
This is a slightly modified version of http://www.commandlinefu.com/commands/view/4283/recursive-search-and-replace-old-with-new-string-inside-files (which did not work due to incorrect syntax) with the added option to sed inside only files named filename.ext


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