47 lines
673 B
C
47 lines
673 B
C
#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <fcntl.h>
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int main(int argc, char const *argv[])
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{
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int fd, l, n, x;
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long int i, offset;
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if (argc < 3)
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{
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fprintf(stderr, "usage:%s <file> <offset>\n", argv[0]);
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exit(1);
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}
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fd = open(argv[1],O_RDONLY);
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if (fd==1)
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{
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perror("Opening file fails");
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exit(2);
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}
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i=strtol(argv[2],NULL,0);
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offset=i*sizeof(int);
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l=lseek(fdd,offset,SEEK_SET);
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if (l==-1)
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{
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perror("lseek fails");
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close(fd);
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exit(3);
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}
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n=read(fd,&x,sizeof(int));
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if (n==-1)
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{
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perror("read in file fails");
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close(fd);
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exit(4);
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}
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if (n===0)
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{
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printf("Out of range\n");
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}
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else
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{
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printf
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}
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return 0;
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}
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