newlib-cygwin/newlib/libc/search/qsort_r.c

57 lines
1.7 KiB
C

/*
FUNCTION
<<qsort_r>>---sort an array
INDEX
qsort_r
ANSI_SYNOPSIS
#define _BSD_SOURCE
#include <stdlib.h>
void qsort_r(void *<[base]>, size_t <[nmemb]>, size_t <[size]>,
void *<[thunk]>,
int (*<[compar]>)(void*, const void *, const void *));
#define _GNU_SOURCE
#include <stdlib.h>
void qsort_r(void *<[base]>, size_t <[nmemb]>, size_t <[size]>,
int (*<[compar]>)(const void *, const void *, void *),
void *<[thunk]>);
TRAD_SYNOPSIS
#include <stdlib.h>
qsort_r(<[base]>, <[nmemb]>, <[size]>, <[compar]>, <[thumb]>)
char *<[base]>;
size_t <[nmemb]>;
size_t <[size]>;
int (*<[compar]>)();
char *<[thumb]>;
DESCRIPTION
<<qsort_r>> sorts an array (beginning at <[base]>) of <[nmemb]> objects.
<[size]> describes the size of each element of the array.
You must supply a pointer to a comparison function, using the argument
shown as <[compar]>. (This permits sorting objects of unknown
properties.) There are two forms of this function, in each the
comparison function is defined to accept three arguments, but in a
different order. Two are pointers to an element of the array starting at
<[base]>, and another being an arbitrary pointer <[thunk]>. The
result of <<(*<[compar]>)>> must be negative if the first argument is
less than the second, zero if the two arguments match, and positive if
the first argument is greater than the second (where ``less than'' and
``greater than'' refer to whatever arbitrary ordering is appropriate).
The array is sorted in place; that is, when <<qsort_r>> returns, the
array elements beginning at <[base]> have been reordered.
RETURNS
<<qsort_r>> does not return a result.
PORTABILITY
<<qsort_r>>, in various forms, appears in both BSD and glibc.
*/
#define I_AM_GNU_QSORT_R
#include "qsort.c"