I cannot figure out why program control does not reach the third printf, right after the for loop.
Why won't the third printf
print?
If I change the for loop to while loop, it still will not print.
Here is the program and output:
main()
{
double nc;
printf ("Why does this work, nc = %f\n", nc);
for (nc = 0; getchar() != EOF; ++nc)
{
printf ("%.0f\n", nc);
}
printf ("Why does this work, nc = %f", nc);
}
The output is:
Why does this work, nc = 0.000000
test
0
1
2
3
4
It works fine for me, how are you trying to termintate the program? The for
-loop should end once EOF
is detected as input by getchar()
.
EOF
is Control-Z
( ^Z
) under Windows and Control-D
( ^D
) under Linux/Unix. Once I enter this, the loop terminates and I get the final printf()
to display its output.
As a final note (as mentioned by @DanielFisher too), add a '\\n'
at the end of your final printf()
call as it may be required by your particular implementation or otherwise the program's behavior might be undefined (thanks to @KeithThompson and @AndreyT pointing this out in the comments):
printf ("Why does this work, nc = %f\n", nc);
printf
is buffered, that's why the final line may not be displayed. That means a call to printf
may not result in a direct output as the function accumulates data before putting it in the output (your terminal).
A call to fflush
after your last printf will put everything that remains in the buffer in your terminal. Also, the buffer is flushed every time you ask for a newline.
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