NAME

qsort − quicker sort

SYNOPSIS

qsort(base, nel, width, compar)
char ∗base;
int (∗compar)();

DESCRIPTION

qsort is an implementation of the quicker-sort algorithm.  It sorts a table of data in place. 

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

NOTES

The pointer to the base of the table should be of type pointer-to-element, and cast to type pointer-to-character. 
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 order in the output of two items which compare as equal is unpredictable.

SEE ALSO

bsearch(3), lsearch(3), string(3), sort(1)

Sun Release 3.2  —  Last change: 15 April 1986