Commands tagged bash, ksh, function (1)

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launch bash without using any letters
ry4an@four:~$ echo $SHLVL 1 ry4an@four:~$ ${0/-/} ry4an@four:~$ echo $SHLVL 2

UPS Tracking Script

reverse-i-search: Search through your command line history
"What it actually shows is going to be dependent on the commands you've previously entered. When you do this, bash looks for the last command that you entered that contains the substring "ls", in my case that was "lsof ...". If the command that bash finds is what you're looking for, just hit Enter to execute it. You can also edit the command to suit your current needs before executing it (use the left and right arrow keys to move through it). If you're looking for a different command, hit Ctrl+R again to find a matching command further back in the command history. You can also continue to type a longer substring to refine the search, since searching is incremental. Note that the substring you enter is searched for throughout the command, not just at the beginning of the command." - http://www.linuxjournal.com/content/using-bash-history-more-efficiently

Find out when your billion-second anniversary is (was). (on OS X)
This is the same command as this one, but for OS X. http://www.commandlinefu.com/commands/view/3053/find-out-when-your-billion-second-anniversary-is-was.

Remote screenshot
Admittedly, I'd never have thought of this without the earlier examples, but here's one that you can execute from your workstation to just display the image from another, without separately doing a file transfer, etc. By the way, I hear a loud beep coming from the other room, so I guess it's not too stealthy :-D

function to compute what percentage of X is Y? Where percent/100 = X/Y => percent=100*X/Y
This function make it easy to compute X/Y as a percentage. The name "wpoxiy" is an acronym of "what percentage of X is Y"

pretend to be busy in office to enjoy a cup of coffee

Does a traceroute. Lookup and display the network or AS names and AS numbers.
From the man page. lft ? display the route packets take to a network host/socket using one of several layer-4 protocols and methods; optionally show heuristic network information in transitu -A Enable lookup and display of of AS (autonomous system) numbers (e.g., [1]). This option queries one of several whois servers (see options 'C' and 'r') in order to ascertain the origin ASN of the IP address in question. By default, LFT uses the pWhoIs service whose ASN data tends to be more accurate and more timely than using the RADB as it is derived from the Internet's global routing table. -N Enable lookup and display of network or AS names (e.g., [GNTY-NETBLK-4]). This option queries Prefix WhoIs, RIPE NCC, or the RADB (as requested). In the case of Prefix WhoIs or RADB, the network name is displayed. In the case of RIPE NCC, the AS name is displayed.

FizzBuzz One-liner

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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