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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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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Variables

For Raspberry Pi with a 32-bit processor Name C++ Bytes Range bool 1 true or false signed char int8_t 1 -128 to 127 unsigned char uint8_t 1 0 to 255 short int int16_t 2 -32768 to 32767 unsigned short int uint16_t 2 0 to 65535 int int32_t 4 -2147483648 to 2147483647 unsigned int uint32_t 4 0 […]

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