# Child Pages

## Programs

 ddclient How to install and use ddclient, a Perl program for updating Dynamic DNS services. export Making variables global and available to other programs, creating and manipulating environment variables. find A program for finding files and folders on your computer that match certain patterns. rsync How to use rsync, a program for synchronising (aka clever copying/deletion) of files/directories. sed sed is the go-to program when wanting to modify the contents of text files.

Coming soon…

# System Calls

System calls provide the Linux between user space and kernal space.

See http://docs.cs.up.ac.za/programming/asm/derick_tut/syscalls.html for a comprehensive table of all the Linux system calls.

# tty

The tty command displays the file name of the terminal connected to the standard input (i.e. the current terminal).

To list your open streams, type

 in the above example represents your bash shell PID.

# SCP

scp (secure copy) is a way of copying files from one computer to another, in a similar manner to the SSH interface. The command has the following syntax:

Note that remote files have to be prefixed with username@address:. Only one of original-file and destination-file can be remote, at least one has to be local. Here is an example which copies a local file to a remote computer.

To copy whole directories, you can use the -r flag.

# SSH

JuiceSSH is a great SSH app for Andriod phones. It is a fully-featured terminal client, with support for SSH, local shell, Mosh and Telnet.

# A Better Bash

One of my must-dos when using bash is to make the up and down arrow keys search through history in an auto-complete fashion with what you have already typed on the command line. To do this, add the following lines of code anywhere in your .bashrc file (which is located in the root user directory of Linux systems).

# Remote Desktop

Install tightvncserver.

Then run tightvnc server by just typing:

To stop a vncserver, type:

# Samba

Samba is software which allows file and printer sharing between computers, normally between Windows and *nix systems. The name samba goes from the acronym SMB (server message block), which is the standard protocol Microsoft uses for networked files.

Samba can be installed by typing:

# Avahi

Avahi includes a service for multi-cast DNS discovery.

# Connecting A USB-To-Serial Adapter To A Linux Terminal

Linux should automatically recognise most USB-To-Serial Adapters when you plug them in and create a device in /dev/ called something like ttyUSB0.

This is what you will use to send/receieve information over the serial link.

Programs you can use include:

• putty
• minicom