Commands by flojo (3)

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Change every instance of OLD to NEW in file FILE
Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

Download a file securely via a remote SSH server
This command will download $file via server. I've used this when FTP was broken at the office and I needed to download some software packages.

prevent large files from being cached in memory (backups!)
We all know... $ nice -n19 for low CPU priority.   $ ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do $ cachedel   To check the cache status of a file, do $ cachestats

Extract public key from private
This will extract the public key that is stored in the private key using openssl.

Get a list of ssh servers on the local subnet
Scan the local network for servers who have the ssh port open.

Simulate typing

unpack all rars in current folder

Create the directoty recursively

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)

List files accessed by a command
Can be run as a script `ftrace` if my_command is substrituted with "[email protected]" It is useful when running a command that fails and you have the feeling it is accessing a file you are not aware of.


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