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Exercise 4.8 - getch and ungetch handling pushback character
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Question
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Suppose that there will never be more than one character of pushback. Modify
getch and ungetch accordingly.
.. literalinclude:: cprogs/ex_4.8_getch_ungetch_pushback.c
:language: c
Explanation
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This program maintains a character buffer `char buf=0` which holds a single
character from the input. The function `ungetch(c)` when called places the
character in the input and `getch()`, if it finds the character in the buf,
returns it or it calls `getchar` to get character from the user.
Visualize It
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.. raw:: html
Try It
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.. raw:: html