======================================= 5.15 fold upper and lower case together ======================================= Question ======== Add the option -f to fold upper and lower case together, so that case distinctions are not made during sorting; for example, a and A compare equal. .. coderun:: cprogs/ex_5.15_sortfnr.c :language: c :tab-width: 4 Explanation =========== This is a sort function, which sorts the given input lines. But this function adds a flag `-f` which introduces case insensitive folding. :: ./ex_5.15_sortfnr -f hello Hello Apple Apple Hello hello Visualize the Concept --------------------- .. raw:: html