Commands by root (53)

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alt + 1 .
alt + number + dot will insert last command argument at $number place, alt + 0 + . will print last command name. For example $ ls /tmp /var $ ls /usr /home alt + 1 + . will result in '/usr' , if you press alt + . again, it will result in '/tmp' alt + 0 + . -> 'ls'

Print only the odd lines of a file (GNU sed)
The tilde address operator is an extension of GNU sed. It won't work with POSIX sed.

Create an animated gif from a Youtube video
requires "youtube-dl" -- sure you can do this with wget and some more obscurity but why waste your time when this great tool is available? the guts consist of mplayer converting a video to a gif -- study this command and read the man page for more information $ mplayer video.flv -ss 00:23 -endpos 6 -vo gif89a:fps=5:output=output.gif -vf scale=400:300 -nosound generates a 6 second gif starting at 23 seconds of play time at 5 fps and a scale of 400x300 start time (-ss)/end time (-endpos) formats: 00:00:00.000 end time should be relative to start time, not absolute. i.e. -endpos 5 == seconds after 0:42 = 0:47 end point play with fps and scale for lower gif sizes the subshell is a solution for the -b flag on youtube-dl which downloads the best quality video, sometimes, which can be various video formats $(ls ${url##*=}*| tail -n1)

Validate all XML files in the current directory and below
If everything validates, there's no output. Can be handy to run on a cron job set up to email output.

Count lines of source code excluding blank lines and comments
Much more accurate than other methods mentioned here straight out of the box.

Make the "tree" command pretty and useful by default
I got really tired of having tree always show me tons of .svn and .git stuff that I don't care about. With this alias, "tree" uses pretty colors, snazzy line graphics, and ignores any source control and package mumbojumbo. (Customize the *.*.package glob, of course.)

Most Commonly Used Grep Options
This is very helpful to place in a shell startup file and will make grep use those options all the time. This example is nice as it won't show those warning messages, skips devices like fifos and pipes, and ignores case by default.

list all file-types (case-insensitive extensions) including subdirectories

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

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)


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