The Single UNIX ® Specification, Version 2
Copyright © 1997 The Open Group


qsort - sort a table of data


#include <stdlib.h>

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


The qsort() function sorts an array of nel objects, the initial element of which is pointed to by base. The size of each object, in bytes, is specified by the width argument.

The contents of the array are sorted in ascending order according to a comparison function. The compar argument is a pointer to 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 0, if the first argument is considered respectively less than, equal to, or greater than the second. If two members compare as equal, their order in the sorted array is unspecified.


The qsort() function returns no value.


No errors are defined.




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






Derived from Issue 1 of the SVID.

UNIX ® is a registered Trademark of The Open Group.
Copyright © 1997 The Open Group
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