| 14.1 | Write a test program that illustrates your system's behavior when a process is blocked trying to write-lock a range of a file and additional read-lock requests are made. Is the process requesting a write lock starved by the processes read-locking the file?
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| 14.2 | Take a look at your system's headers and examine the implementation of select and the four FD_ macros.
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| 14.3 | The system headers usually have a built-in limit on the maximum number of descriptors that the fd_set data type can handle. Assume that we need to increase this limit to handle up to 2,048 descriptors. How can we do this?
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| 14.4 | Compare the functions provided for signal sets (Section 10.11) and the fd_set descriptor sets. Also compare the implementation of the two on your system.
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| 14.5 | How many types of information does getmsg return?
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| 14.6 | Implement the function sleep_us, which is similar to sleep, but waits for a specified number of microseconds. Use either select or poll. Compare this function to the BSD usleep function.
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| 14.7 | Can you implement the functions TELL_WAIT, TELL_PARENT, TELL_CHILD, WAIT_PARENT, and WAIT_CHILD from Figure 10.24 using advisory record locking instead of signals? If so, code and test your implementation.
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| 14.8 | Determine the capacity of a pipe using nonblocking writes. Compare this value with the value of PIPE_BUF from Chapter 2.
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| 14.9 | Recall Figure 14.28. Determine the break-even point on your system where using writev is faster than copying the data yourself and using a single write.
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| 14.10 | Run the program in Figure 14.32 to copy a file and determine whether the last-access time for the input file is updated.
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| 14.11 | In the program from Figure 14.32, close the input file after calling mmap to verify that closing the descriptor does not invalidate the memory-mapped I/O.
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