Hey hombres. I feel a bit embarassed to ask something so simple,but i need help with qsort.
As you will understand,im trying to sort my table made of "catPage" structs,which are read from keyboard,comparing the lName strings.
First i print the struct array unsorted,then sorted,but what i see printed is 2 times the same unsorted array. In other words,i get no compiler errors from qsort,but it simply does nothing. (I have been stuck here for a good 4 hours,i decided to give up and ask help :P)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct catPage {

       char name[20];
       char lName[20];
       ///char address[40];
       int pNumber;
       ///char email[20];

struct catPage catalogue[50];
int catFreeEntry=3;
int rep;
int i;
int choice=3;
void appendEntry(struct catPage ca);
struct catPage getCatPage(struct catPage ca);
const int myCompare (const void *a, const void *b) ;
void qsort(void *base, size_t count, size_t size, int (*comp)(const void *e1, const void *e2));

int main(int argc, char *argv[])
    struct catPage cat;
    struct catPage catalogue[50];
    while(choice!=0) {
                     printf("\n1 to add Contact(s), 2 to view contacts,0 to exit");
                     if (choice==1){
                     printf("How many contacts to add?\n");
                     if (rep<0||rep>100) break;
                     for (i=0;i<rep;i++) {

                     if (choice==2){
                     for (i=0;i<catFreeEntry;i++){
                     printf("%-8s -- %8s     %8d\n",catalogue[i].name,catalogue[i].lName,catalogue[i].pNumber);
                     printf("\n <test>2o format ->\n");
                     size_t structs_len = sizeof(catalogue) / sizeof(struct catPage);
                     qsort (catalogue,structs_len,sizeof(struct catPage),myCompare);
                     for (i=0;i<catFreeEntry;i++){
                     printf("%-8s -- %8s     %8d\n",catalogue[i].name,catalogue[i].lName,catalogue[i].pNumber);

  return 0;

struct catPage getCatPage(struct catPage ca){

       printf("last name\n");

       return ca;

void appendEntry (struct catPage ca) {

int myCompare (const void *a, const void *b) const {
    struct catPage *ia = (struct catPage *)a;
    struct catPage *ib = (struct catPage *)b;
    return strcmp(ia->lName, ib->lName);

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Change the

int catFreeEntry=3;

to =0; ,i was just trying something else and forgot to change it back...

The most immediate problem is on lines 14 and 28; the local definition of catalogue shadows the global definition (didn't you get a compiler warning?). I am not sure what exactly happens, but it is pretty much possible that you sort one array, and print another. For example, appendEntry surely fills up the global one; which one is passed to qsort, I have no idea. Verify it with the debugger.

On a side note, your sorting setup is incorrect. You want to sort only rep records, not the whole array.
On another side note, why are you redeclaring qsort? It is already declared in stdlib.h.

hey nez.Thanks for fast reply.Although you are right,no line 28 doesn't cause the problem. But you may be right. If the qsort function could not be executed for some reason (eg wrong comp function) i would get compiler error.But i dont get any so qsort must be used on some other (?) array..Any suggestions?

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