Commands by rolanda (5)

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Viewable terminal session over network.
connect to it with any network command (including web browser - if you don't mind weird formatting) curl 127.0.0.1:9876 nc 127.0.0.1 9876

View all date formats, Quick Reference Help Alias
If you have used bash for any scripting, you've used the date command alot. It's perfect for using as a way to create filename's dynamically within aliases,functions, and commands like below.. This is actually an update to my first alias, since a few commenters (below) had good observations on what was wrong with my first command. # creating a date-based ssh-key for askapache.github.com $ ssh-keygen -f ~/.ssh/`date +git-$USER@$HOSTNAME-%m-%d-%g` -C 'webmaster@askapache.com' $ # /home/gpl/.ssh/git-gplnet@askapache.github.com-04-22-10 # create a tar+gzip backup of the current directory $ tar -czf $(date +$HOME/.backups/%m-%d-%g-%R-`sed -u 's/\//#/g'

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

Daily watch "question pour un champion" (French TV show)
kaffeine could be replaced by any player able to read mms stream

Mount a partition from within a complete disk dump
Suppose you made a backup of your hard disk with dd: dd if=/dev/sda of=/mnt/disk/backup.img This command enables you to mount a partition from inside this image, so you can access your files directly. Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

32 bits or 64 bits?
Easy and direct way to find this out.

sudo for launching gui apps in background
Need package: gksu Note: Launching gui app in background that needs sudo, won't work great with our old friendly style of launching: $ sudo gedit /etc/passwd & because this would put sudo in background ! Using gksudo as demonstrated, would popup a gui sudo window. May be this is a common knowledge, but not knowing this frustrated me during my newbie year.

Remove executable bit from all files in the current directory recursively, excluding other directories
Useful if you have copied files from an OS without a permission structure (for example, DOS) and you need to disable all executable files but want to be able to descend into your directories.

Backup all MySQL Databases to individual files
Backs up all databases, excluding test, mysql, performance_schema, information_schema. Requires parallel to work, install parallel on Ubuntu by running: sudo aptitude install parallel


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