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/* Initialization of packed structs */
#include <stdio.h>
/* Simple packing */
struct __packed__(1) s1 { unsigned short x; int y; char z; };
struct s1 s1 = { 2345, -12345678, 'x' };
void test1(void)
{
printf("s1 = {x = %d, y = %d, z = '%c'}\n\n", s1.x, s1.y, s1.z);
}
/* Now with byte-swapped fields */
struct __packed__(1,1,1) s3 {
unsigned char x;
unsigned short y;
unsigned int z;
signed short v;
signed int w;
char * p;
unsigned int t[3];
unsigned char s[2];
};
struct s3 s3 = {
42, 123, 456789, -333, -314159, 0,
{ 111, 222, 333 },
{ 'o', 'k' }
};
void test3(void)
{
printf("s3 = {x = %u, y = %u, z = %u, v = %d, w = %d, p is %s, t = {%d,%d,%d}, s = {'%c','%c'}}\n\n",
s3.x, s3.y, s3.z, s3.v, s3.w,
(s3.p == 0 ? "ok" : "BAD"),
s3.t[0], s3.t[1], s3.t[2],
s3.s[0], s3.s[1]);
}
/* Back to normal */
struct s4 { unsigned short x; int y; double z; };
struct s4 s4 = { 123, -456789, 3.14159 };
void test4(void)
{
printf("s4 = {x = %d, y = %d, z = %.5f}\n\n", s4.x, s4.y, s4.z);
}
/* Test harness */
int main(int argc, char ** argv)
{
test1();
test3();
test4();
return 0;
}
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