34 lines
1.2 KiB
Groff
34 lines
1.2 KiB
Groff
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NAME
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qsort - quicker sort
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SYNTAX
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void qsort ((char *) base, nel, sizeof (*base), compar)
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unsigned nel;
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int (*compar)( );
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DESCRIPTION
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Qsort is an implementation of the quicker-sort algorithm.
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It sorts a table of data in place.
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Base points to the element at the base of the table. Nel is
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the number of elements in the table. Compar is the name of
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the comparison function, which is called with two arguments
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that point to the elements being compared. As the function
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must return an integer less than, equal to, or greater than
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zero, so must the first argument to be considered be less
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than, equal to, or greater than the second.
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NOTES
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The pointer to the base of the table should be of type
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pointer-to-element, and cast to type pointer-to-character.
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The comparison function need not compare every byte, so
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arbitrary data may be contained in the elements in addition
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to the values being compared.
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The order in the output of two items which compare as equal
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is unpredictable.
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SEE ALSO
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bsearch(3C), lsearch(3C), string(3C).
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sort(1) in the UNIX System V User Reference Manual.
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WARNING
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The total size of the table (nel x sizeof(*base)) must be
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less than 65536 in small and large model programs.
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