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Linux: Hide Processes From Other Users

I run a multi-user system. Most users access resources using ssh client. How can I stop leaking process information to all users on Linux operating systems? How do I prevent users from seeing processes that do not belong to them on a Debian/Ubuntu/RHEL/CentOS Linux server?
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Connect To Amazon AWS EC2 Instance From a CentOS / RHEL Using SSH Client

I have created/launched Amazon Machine Image (AMI) instance powered by a CentOS/RHEL/Red Hat Enterprise Linux. How can I connect to my instance using OpenSSH Linux/Unix/OSX ssh client?
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Linux / Unix: Find And List All Hidden Files Recursively

I am a new Unix system shell user. I need to find and list all hidden files including directories on a Linux or Unix-like system. How can I recursively list all hidden files and directories? How do I save result in a text file?
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Unix: Find Directory Name From Path

I am a new Unix shell programer. How can I extract the directory name from a full path (say /nas01/data/backups/file.tar.gz)? How do I get directory name from its path on a Linux or Unix-like system?
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scp: Do not Overwrite Existing File On Linux or Unix System

I am a new Linux user. I use scp to upload files to net-storage provided CDN company. I do not want to overwrite the existing files. How can I prevent overwriting of files when using scp command under Linux, Mac OS X or Unix like operating systems?
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Vi / Vim: Wipe and Undo All Changes Since Opening a File

I am a new vi / vim text editor user and I know how to quit without saving changes. What if I want to wipe out all of the edits I have made in a session and get back to the original file? How do I wipe all changes since opening a file?
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Linux / Unix: Use rsync Command Over FTP

How do I use rsync command to sync files to a remote host called web-42.vps running VSFTPD ftp server? Can you give me rsync ftp example for Unix like operating systems?
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I'm setting up server on an Amazon EC2 compute instance powered by Suse Enterprise Linux server. I am using the following command to login into the my EC2 compute from OS X/Ubuntu desktop:

ssh -i suse-ec2-server-jp.pem root@ec2-xx-yy-zzz-yyy.compute-1.amazonaws.com

I am getting the following error:
Permissions 0440 for 'suse-ec2-server-jp.pem' are too open.
It is recommended that your private key files are NOT accessible by others.
This private key will be ignored.
bad permissions: ignore key: suse-ec2-server-jp.pem

How do I fix this problem and login using ssh command?
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Linux / Unix Bash Shell List All Builtin Commands

Builtin commands are contained within the bash shell itself. How do I list all bash builtin commands under Linux / Apple OS X / *BSD / Unix like operating systems without reading large bash man page?
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Linux: Start Command In Background

I am a new Linux command line user. How do I start or run command in the background so that I can access command prompt immediately?
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