Shared Memory Between C Application And PHP Web Server

A fully working demonstration of a php page running in Apache on the Raspberry Pi being able to safely access shared memory created by a C application also running on the Raspberry Pi.  A semaphore is used to avoid access conflicts. The C program creates a byte array.  The php shared memory functions work using strings, […]

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WinSCP-Transfering Files From Windows PC’s

WinSCP To avoid having to use a USB stick to transfer files from your windows machine to your Raspberry Pi use WinSCP Get WinSCP from here and install it. When it opens setup the following: Session File Protocol: SCP Host name: The IP address of you Raspberry Pi User name: pi Password: raspberry Advanced > SCP /Shell […]

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Using Semaphores

Semaphores allow processes to avoid clashes when accessing shared resources, for instance shared memory. Generating A Random Key Humans aren't very good at picking random values so use a site like this one: www.random.org/integers/ It won't do a 32bit 1 to 2147483647, but it will do 1 to 1000000000 Simple Example Of Creating & Using […]

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Shared Memory

Shared memory allows two unrelated processes to access the same logical memory and is a very efficient way of transferring data between two running processes. If one process writes to the shared memory, the changes immediately become visible to any other process that has access to the same shared memory. The only catch is that by […]

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Using the PWM Pin

Important Note The PWM pin available on the GPIO header is shared with the Audio system. This means that you can't use PWM output and play audio through the 3.5mm jack at the same time. Good resources http://xoblo.gs/rpi/2012/09/01/pwm-driver-part-2:-research/ http://learn.adafruit.com/adafruit-raspberry-pi-educational-linux-distro/occidentalis-v0-dot-2  

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.GTK General

GTK+ is a library for creating graphical user interfaces. The GTK+ library is also called the GIMP Toolkit.  GTK application need to run within the GUI environment (startx). The GTK library is, well, kinda basic.  It you're coming from a windows or mac environment then be prepared for a shock, gtk is no where near […]

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