CSCI 4061 Lab06: File Stat via stat() / lstat()

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                            LAB 06 QUESTIONS
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Lab Instructions
================

  Follow the instructions below to experiment with topics related to
  this lab.
  - For sections marked QUIZ, fill in an (X) for the appropriate
    response in this file. Use the command `make test-quiz' to see if
    all of your answers are correct.
  - For sections marked CODE, complete the code indicated. Use the
    command `make test-code' to check if your code is complete.
  - DO NOT CHANGE any parts of this file except the QUIZ sections as it
    may interfere with the tests otherwise.
  - If your `QUESTIONS.txt' file seems corrupted, restore it by copying
    over the `QUESTIONS.txt.bk' backup file.
  - When you complete the exercises, check your answers with `make test'
    and if all is well, create a zip file with `make zip' and upload it
    to Gradescope. Ensure that the Autograder there reflects your local
    results.
  - IF YOU WORK IN A GROUP only one member needs to submit and then add
    the names of their group.


QUIZ Questions on switch_stdout.c
=================================

  Analyze the `filestats.c' program. Compile and run it via
  ,----
  | > make filestats
  | ...
  | > ./filestats somefile.txt
  | ...
  | > ./filestats a_dirname/
  `----

  You may wish to create some symbolic links to files as well and run
  `filestats' on the links to see the behavior using the file.
  ,----
  | > touch myfile.txt
  | > ln -s myfile.txt symlink_to_myfile.txt
  | 
  | > ./filestats myfile.txt
  | ...
  | > ./filestats symlink_to_myfile.txt
  `----

  Finally, you can contrast the behavior of `filestats.c' to the shell
  command `stat' which provides similar functionality.

  Answer the following questions about how the system call works.


stat() vs lstat()
~~~~~~~~~~~~~~~~~

  Consult the manual pages / documentation and choose which of the
  following best describes the difference between `stat()' and
  `lstat()'.
  - ( ) `stat()' reports integer data / size on files while `lstat()'
    will report "long" data in the form of `long' return types
  - ( ) `stat()' will follow symbolic links and report data on the
    linked file while `lstat()' will report information on the link
    itself
  - ( ) `stat()' reports all information on a file whereas `lstat()' is
    faster but "l-imited" in the information it returns.
  - ( ) `stat()' immediately produces the data on a file while `lstat()'
    is a "lazy" call which will only complete when the data is actually
    used


File Size
~~~~~~~~~

  How does `stat() / lstat()' report the Size of a file?
  - ( ) An integer is passed to the calls to be set to the size
  - ( ) The return value is the number of bytes in the file
  - ( ) The size is printed to standard output during the function call
  - ( ) The field `sb.st_size' contains the number of bytes in file


File Kind
~~~~~~~~~

  `stat() / lstat()' report the "kind" of file being queried. How is
  this information used in `filestats.c'?
  - ( ) The field `sb.st_filetype' is set to a string like "file" or
    "pipe" to indicate the type of a file and that field can be printed
    directly
  - ( ) An integer passed in as an address to the call is set to the
    type of the file
  - ( ) The kind is encoded in the `sb.st_mode' field of the struct and
    macros are used to distinguish the kind and print an appropriate
    message.
  - ( ) The kind is encoded in the `sb.st_mode' field of the struct and
    functions are used to distinguish the kind and print an appropriate
    message.

  Which one of the following is NOT a file "kind" reported by `stat() /
  lstat()'
  - ( ) Directory
  - ( ) Binary
  - ( ) Socket
  - ( ) Symbolic Link (symlink)


mtime / ctime
~~~~~~~~~~~~~

  Do some research and determine the difference between the `ctime' and
  `mtime' alteration times that are reported by `stat() /
  lstat()'. Which of the following best describes this difference:
  - ( ) `mtime' and `ctime' actually always report the same time and
    their redundancy is a historical oddity.
  - ( ) `mtime' indicates the last time that the file was moved from one
    directory to another while `ctime' indicates the last change to the
    data in the file
  - ( ) `mtime' is the last time of modification when data was altered
    in the file while `ctime' is the last access time when data was read
    from the file
  - ( ) `mtime' is when the actual data of a file changes while `ctime'
    is associated with permissions, links, or other meta data changes
    associated with the file.


Additional Items to Observe
~~~~~~~~~~~~~~~~~~~~~~~~~~~

  The function `ctime()' and `strmode()' both use an interesting
  technique to make it possible to easily produce a printable string for
  situations like those in `filestats.c'.  Time permitting, examine the
  source code for `strmode()' in `strmode.c' and discuss with a TA how a
  string is returned but there is no requirement to free that string.


CODE
====

  None for this lab