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qsort(3C)                                                            qsort(3C)

NAME
     qsort - quicker sort

SYNOPSIS
     #include <stdlib.h>

     void qsort (void* base, size_t nel, size_t width, int (*compar)
         (const void *, const void *));

DESCRIPTION
     qsort is an implementation of the quicker-sort algorithm.  It sorts a
     table of data in place.  The contents of the table are sorted in
     ascending order according to the user-supplied comparison function.

     base points to the element at the base of the table.  nel is the number
     of elements in the table.  width specifies the size of each element in
     bytes.  compar is the name of the comparison function, which is called
     with two arguments that point to the elements being compared.  The
     function must return an integer less than, equal to, or greater than zero
     to indicate if the first argument is to be considered less than, equal
     to, or greater than the second.

     The contents of the table are sorted in ascending order according to the
     user supplied comparison function.

SEE ALSO
     sort(1), bsearch(3C), lsearch(3C), string(3C)

NOTES
     The comparison function need not compare every byte, so arbitrary data
     may be contained in the elements in addition to the values being
     compared.

     The use of void * pointer types circumvents the need for casts in older
     versions of qsort.

     The relative order in the output of two items that compare as equal is
     unpredictable.

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