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#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
int
fill_with_zeroes(const char *filename)
{
int fd = open(filename, O_WRONLY);
if(fd == -1) {
fprintf(stderr, "shred: %s: %s\n", filename, strerror(errno));
return 1;
}
struct stat stat_struct; /* What name should i use? */
if(stat(filename, &stat_struct) == -1) {
fprintf(stderr, "shred: %s: %s\n", filename, strerror(errno));
return 1;
}
long int bytes_to_write = stat_struct.st_size;
for(int i = 0; i < bytes_to_write; i++)
if(write(fd, "\0", 1) == -1) {
fprintf(stderr, "shred: %s: %s\n", filename, strerror(errno));
return 1;
}
if(fsync(fd) == -1) {
fprintf(stderr, "shred: %s: %s\n", filename, strerror(errno));
return 1;
}
close(fd);
return 0;
}
int
main(int argc, char *argv[])
{
int c = getopt(argc, argv, "u"); /* TODO: add -f */
if(fill_with_zeroes(argv[optind]) != 0) {
return 1;
}
if(c == 'u')
if(remove(argv[optind]) == -1) {
fprintf(
stderr, "shred: %s: %s\n", argv[optind], strerror(errno));
return 1;
}
return 0;
}
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