47 lines
637 B
C
47 lines
637 B
C
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#include <fcntl.h>
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#include <unistd.h>
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#include <stdio.h>
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int readFile(int fd){
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char buff[1024];
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ssize_t rbit = pread(fd, buff, 1024, 0);
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if(rbit < 0){
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printf("Error in reading file\n");
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return -1;
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}
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buff[rbit] = '\0';
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printf("rbit: %ld %s\n", rbit, buff);
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return 0;
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}
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int main(void){
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int fd = open("./test/fileat", O_RDWR | O_SYNC);
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if(fd < 0){
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printf("Error in opening file fileat.\n");
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return -1;
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}
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readFile(fd);
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ssize_t wbit = pwrite(fd, "How", 3, 0);
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if(wbit < 0) {
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printf("Error in writing file.\n");
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return -1;
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}
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readFile(fd);
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close(fd);
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return 0;
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}
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