35 lines
669 B
C
35 lines
669 B
C
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#include <stdio.h>
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#include <string.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <fcntl.h>
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#ifndef INITIAL_LIMIT
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# define INITIAL_LIMIT 1025
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#endif
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char buf[2*INITIAL_LIMIT];
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write_to_file(int id) {
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char link[64];
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char * links = "/proc/self/fd/";
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sprintf(link, "%s", links);
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sprintf(link+strlen(links), "%d", id);
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//printf("link=%s\n", link);
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readlink(link, buf, INITIAL_LIMIT);
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//printf("buf=%s\n", buf);
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close(id);
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id = open(buf, O_WRONLY);
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write(id, "Hello world!\n", 13);
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close(id);
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}
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int main(int argc, char * argv[]) {
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int id = open("tmp.txt", O_RDONLY);
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write_to_file(id);
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return (0);
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}
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