[possibly OT] the comparison function in quicksort

[Debashish Chakravarty]

Would it have been a good idea if the comparison function in quicksort
took three const void * parameters in, the third one for extra
information that might be required to compare the two objects, I think
the only way one can pass the information is by using global or static
variables.

 

[Ben Pfaff]

Would it have been a good idea if the comparison function in quicksort

You mean qsort().

took three const void * parameters in, the third one for extra
information that might be required to compare the two objects, I think
the only way one can pass the information is by using global or static
variables.

Yes, it would be a good idea. It is too bad that it doesn't. It
is sometimes difficult to effectively use qsort() and bsearch()
for this very reason. Most well-designed C abstract data type
extension libraries have such a mechanism for this very reason.