pointed out by bde:
- Ask for user confirmation before adjusting to a head/cylinder
boundary (only when running interactively), and separate this
adjustment from the automatic calculation of c/h/s parameters.
- In sanitize_partition, don't change any values in the slice until
we know that the automatic adjustment will succeed.
- When auto-adjusting, ignore unused slices and give an appropriate
error for other zero-size slices depending on the cause.
- Change dos() to do all of the c/h/s calculations for a whole slice;
this fixes a bug where the ending c/h/s of an unused slice was set
incorrectly.
- When changing the active slice, detect the currently active slice
number instead of always defaulting to slice 4.
- Call fflush(stdout) before calling fgets().
- Test for fgets() returning NULL so we don't loop on EOF.
Reviewed by: bde