Commands by quinncom (3)

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Share your terminal session (remotely or whatever)
Force the user you want to watch doing things into doing his things in a screen session. Then simply attach yourself to that session with the command shown above. Works only if you are on the same machine, of course

Get full directory path of a script regardless of where it is run from
Also resolves symlinks, showing the full path of the link target

Recursive find and replace file extension / suffix (mass rename files)
Find recursively all files in ~/Notes with the extension '.md' and pipe that via xargs to rename command, which will replace every '.md' to '.txt' in this example (existing files will not be overwritten).

Combine all .mpeg files in current directory into one big one.
Good old cat & output redirection. Using this method you can combine all kinds of things - even mpeg files. My video camera makes a series of .mpeg files that are broken into 4gb chunks. Using this command I can easily join them together. Even better, combined with the cp command the files can be copied and joined in one step.

Running scripts after a reboot for non-root users .
Sometimes we may want to run a script when a system reboots . We can simply do this by just scheduling the script using vixie cron with the @reboot option . e.g @reboot I use it to send me an alert message on our prod hosts to send an alert message when the system reboots . @reboot zaman uptime | echo `uptime` | mail -s "`uname -n` got rebooted" [email protected]

eavesdrop
Record off the microphone on a remote computer and listen to it live through your speakers locally.

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)

gzip over ssh
I've kept the gzip compression at a low level, but depending on the cpu power available on the source machine you may want to increase it. However, SQL compresses really well, and I found even with -1 I was able to transfer 40 MiB/s over a 100 mbps wire, which was good enough for me.

Get line count for any file ending with extension recursively rooted at the current directory.

ping as traceroute
This command uses ping to get the routers' IP addresses to the destination host as traceroute does. If you know what I mean..


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