c - sort a 2d array using qsort - seg fault -

i'm trying sort 2d array of strings simplified version looks like, ( dont want change datatype of "namearray" "char *namearray[4]" )

#include <sys/types.h> #include <stdio.h>  int cstring_cmp(const void *a, const void *b) {     const char **ia = (const char **)a;     const char **ib = (const char **)b;     return strcasecmp(*ia, *ib); }  int test() {    char namearray[4][10]={"test","alpha","hyper","city"};  //  int nelem = sizeof(namearray)/sizeof(char *);    int index = 0;     //printf("nelem =%d\n", nelem);     for(index=0; index < 4; index++)    {       printf("-> %s\n", namearray[index]);    }     qsort( &namearray[0], 4, sizeof(namearray[0]), cstring_cmp);     printf("after sort\n");     for(index=0; index < 4; index++)    {       printf("-> %s\n", namearray[index]);    }    return 0 ; } 

( update: changed i'm directly using value(4) instead of calculating nelem. problem getting qsort working. )

the arguments comparison function pointers, rather pointers pointers.

you don't need cast believe, since parameters void *, can assign them local variables , compiler takes care of them.

try this:

int cstring_cmp(const void *a, const void *b) {    const char *ia = a;    const char *ib = b;    return strcasecmp(ia, ib); } 

or rid of local variables if don't need them (only need them if you're planning on adding more code comparison function):

int cstring_cmp(const void *a, const void *b) {   return strcasecmp(a, b); }