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Prints Working after Closing stdio

Question Text​

Why does support/redirect/redirect.c, still print messages to the console after closing file descriptor 1 (stdout)?

Question Answers​

  • because wait_for_input() calls fprintf(stderr, ...), which prints to stderr (file descriptor 2)

  • because the default file descriptors cannot be "truly" closed

  • because the other two default file descriptors are still linked to the console

  • because the wait_for_input() function started printed before closing the stdout file descriptor

Feedback​

If you look at wait_for_input() closely, you'll notice it calls fprintf(stderr, ...). stderr is liked to file descriptor 2, which is left unchanged so we can still write data to it.