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>> SPEAKER: Let's write a program that
tries to copy two strings.

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I've already gotten started by first
printing out "Say something." I next

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call GetString, storing
the return value in s.

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And then I make sure
that s is not null.

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>> Let's next make our copy of S. I'm going
to declare a new variable, t,

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and store in it s.

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I'm next going to claim, with
printf, that I'm going to

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capitalize that copy.

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I'm next going to check that t is at
least greater than 0 in length so that

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I don't accidentally try to capitalize
a letter that's not there.

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Once I'm sure, I'm going to change the
value at t bracket 0 to be the return

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value of toupper, a function that
converts its input to uppercase,

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passing in as its input t bracket 0.

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>> Lastly, I'm going to print out what
the original value was, which, of

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course, was s.

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And then I'm going to print what the
value of the copy is, which is t.

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>> When I now compile and run this program,
I hope to see my original

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input followed by a copy thereof
with only the copy capitalized.

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But let's check.

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Make copy 0, ./ copy 0.

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And I'll provide an input of, say,
hello, but in all lowercase,

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and then hit Enter.

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>> Unfortunately, it seems that both the
original and the copy are now "Hello"

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with a capital H. But that's
clearly not what I typed.

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So apparently, when I capitalized t, I
somehow capitalized s, even though I

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thought I was making a copy
of s and calling it t.

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Surely, something here is wrong.

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But how can we fix?

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