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fixes for Power64
[tridge/junkcode.git]
/
mmap_write.c
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#include <stdio.h>
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#include <unistd.h>
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#include <sys/mman.h>
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#include <fcntl.h>
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#include <sys/file.h>
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int main(int argc, const char *argv[])
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{
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int fd;
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char *p;
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fd = open(argv[1], O_RDWR, 0600);
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if (fd == -1) {
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perror(argv[1]);
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return -1;
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}
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p = mmap(NULL, 4, PROT_WRITE, MAP_SHARED, fd, 0);
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if (p == (void *)-1) {
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perror("mmap");
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return -1;
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}
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p[0]++;
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munmap(p, 4);
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close(fd);
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return 0;
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}