fgets() doesn't call fsync() before getting input

[James Larrowe <larrowe.semaj11@gmail.com>]

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I'm writing a program that prints a dialogue to the screen and then asks
for input. In musl, the dialogue does not show before fgets() is called,
however in glibc it does. That causes a blank prompt and also some
confusion. Attached is a minimal example and a log.

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[-- Attachment #2: minimal-example.c --]
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#include <stdio.h>

int main()
{
	char buf[9];

	fputs("Enter a seven letter word: ", stdout);
	fgets(buf, 9, stdin);
	printf("Your word is %s", buf);
	return 0;
}

[-- Attachment #3: log --]
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chronos@localhost ~/Downloads $ gcc minimal-example.c 
chronos@localhost ~/Downloads $ ./a.out  
Enter a seven letter word: letters
Your word is letters
chronos@localhost ~/Downloads $ musl-gcc minimal-example.c 
chronos@localhost ~/Downloads $ ./a.out 
letters
Enter a seven letter word: Your word is letters