c / intermediate
Snippet
Unions for Type Punning
A union allows different members to share the exact same memory location. This is often used for 'type punning'—interpreting the same binary data as different types (e.g., viewing a float's bit pattern as an integer).
snippet.c
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#include <stdio.h>union DataOverlay {float f;unsigned int i;};int main() {union DataOverlay data;data.f = 1.0f;printf("Float: %f, Bits as Int: 0x%X\n", data.f, data.i);return 0;}
Breakdown
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union DataOverlay
Defines a union where all members share the same memory space.
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data.f = 1.0f;
Sets the shared memory using the float representation.
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data.i
Accesses the exact same bits but interprets them as an unsigned integer.