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Nameqsort — sorts an array Synopsis#include <stdlib.h>
DESCRIPTIONThe The contents of the array are sorted in ascending order
according to a comparison function pointed to by The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second. If two members compare as equal, their order in the sorted array is undefined. NOTESLibrary routines suitable for use as the EXAMPLEFor one example of use, see the example under bsearch(3). Another example is the following example program, which sorts the strings given in its command-line arguments:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>
static int
cmpstringp(const void *p1, const void *p2)
{
/* The actual arguments to this function are "pointers to
pointers to char", but strcmp() arguments are "pointers
to char", hence the following cast plus dereference */
return strcmp(* (char * const *) p1, * (char * const *) p2);
}
int
main(int argc, char *argv[])
{
int j;
assert(argc > 1);
qsort(&argv[1], argc - 1, sizeof(char *), cmpstringp);
for (j = 1; j < argc; j++)
puts(argv[j]);
exit(EXIT_SUCCESS);
}
SEE ALSOsort(1), alphasort(3), strcmp(3), versionsort(3)
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