write_counted_string: avoid undefined behavior in fwrite() call
In C23 and earlier, it is undefined behavior to call fwrite() with a NULL pointer, even if the size to copy is zero bytes.
Closes: #11
Signed-off-by: Alan Coopersmith
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In C23 and earlier, it is undefined behavior to call fwrite() with a NULL pointer, even if the size to copy is zero bytes.
Closes: #11
Signed-off-by: Alan Coopersmith