mirror of
https://github.com/gatieme/LDD-LinuxDeviceDrivers.git
synced 2026-08-19 01:22:36 +08:00
38 lines
583 B
C
38 lines
583 B
C
#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/mman.h>
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#include <unistd.h>
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#define MAP_SIZE 1024*1024
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int main(int argc, char **argv)
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{
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unsigned char *m;
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int i;
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pid_t pid;
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m = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
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for (i = 0; i < MAP_SIZE; i++)
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m[i] = 10;
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pid = fork();
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if (pid == -1) {
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exit(1);
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} else if (pid == 0) {
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sleep(10);
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} else {
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sleep (5);
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/* Cow */
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for (i = 0; i < MAP_SIZE; i++)
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m[i] = 20;
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printf("cow is done in parent pscess\n");
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sleep(10);
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}
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return EXIT_SUCCESS;
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}
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