53 lines
1.0 KiB
C
Executable File
53 lines
1.0 KiB
C
Executable File
#include <stdio.h>
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#include <stdlib.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <sys/file.h>
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#include <sys/types.h>
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#include <sys/stat.h>
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int
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main(int argc, char *argv[])
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{
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int fdin = open("in", O_RDWR);
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if (fdin == -1) {
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return 1;
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}
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double num1, num2;
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// Read the first double
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if (read(fdin, &num1, sizeof(double)) != sizeof(double)) {
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close(fdin);
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return 1;
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}
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// Read the second double
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if (read(fdin, &num2, sizeof(double)) != sizeof(double)) {
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close(fdin);
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return 1;
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}
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// Move the file pointer back to the beginning
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if (lseek(fdin, 0, SEEK_SET) == -1) {
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close(fdin);
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return 1;
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}
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// Write the second double first
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if (write(fdin, &num2, sizeof(double)) != sizeof(double)) {
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close(fdin);
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return 1;
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}
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// Write the first double second
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if (write(fdin, &num1, sizeof(double)) != sizeof(double)) {
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close(fdin);
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return 1;
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}
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close(fdin);
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return 0;
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}
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