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The problems in C are not confined to just the language. Some routines in the standard library have  unsafe semantics. This was dramatically demonstrated in November 1988 by the worm program that wriggled through thousands of machines on the Internet network. When the smoke had cleared and the investigations were complete, it was determined that one way the worm had propagated was through a weakness in the finger daemon, which accepts queries over the network about who is currently logged in. The finger daemon, in.fingerd, used the standard I/O routine gets(). The nominal task of gets() is to read in a string from a stream. The caller tells it where to put the incoming characters. But gets() does not check the buffer space; in fact, it can't check the buffer space. If the caller provides a pointer to the stack, and more input than buffer space, gets() will happily overwrite the stack.  The finger daemon contained the code: main(argc, argv) char *argv[]; { ...