everest% touch sorting.h
everest% make t_quick
        cc  -c sorting.c
        cc  -c quicksort.c
        cc  -o t_quick t_quick.c sorting.o quicksort.o
everest% 

everest% t_quick test10
Quicksort: low = 0, high = 9
Quicksort: low = 0, high = 2
Quicksort: low = 0, high = 0
Quicksort: low = 1, high = 2
Quicksort: low = 1, high = 1
Quicksort: low = 2, high = 2
Quicksort: low = 3, high = 9
Quicksort: low = 3, high = 6
Quicksort: low = 3, high = 5
Quicksort: low = 3, high = 3
Quicksort: low = 4, high = 5
Quicksort: low = 4, high = 4
Quicksort: low = 5, high = 5
Quicksort: low = 6, high = 6
Quicksort: low = 7, high = 9
Quicksort: low = 7, high = 7
Quicksort: low = 8, high = 9
Quicksort: low = 8, high = 8
Quicksort: low = 9, high = 9
   158038549    167400087    613747822    805736951   1008841051 
  1029906275   1030868137   1732205115   1793496490   2021315817 
everest% 

everest% setenv CFLAGS "-DNDEBUG"
everest% touch sorting.h
everest% make -e t_quick
        cc -DNDEBUG -c sorting.c
        cc -DNDEBUG -c quicksort.c
        cc -DNDEBUG -o t_quick t_quick.c sorting.o quicksort.o
everest% 

everest% time t_quick test1k
0.0u 0.0s 0:00 55% 0+0k 0+0io 0pf+0w
everest% 

everest% time t_quick test10k
0.0u 0.0s 0:00 22% 0+0k 5+0io 0pf+0w
everest% 

everest% time t_quick test100k
0.6u 0.0s 0:01 49% 0+0k 27+0io 0pf+0w
everest% 

everest% time t_quick test200k
1.2u 0.0s 0:04 33% 0+0k 51+0io 0pf+0w
everest% 

everest% time t_quick test400k
2.8u 0.0s 0:09 29% 0+0k 100+0io 0pf+0w
everest% 

everest% time t_quick test800k
5.7u 0.1s 0:20 29% 0+0k 198+0io 0pf+0w
everest% 

everest% time t_quick test1.6m
12.1u 0.3s 0:44 28% 0+0k 393+0io 0pf+0w
everest%