Thread: Swicthing data orders...

Ok,

My progs, read data in a file, show content on screen, and now It must save data in another files but in a different orders( the last will be the first record and the first the last....) well here my code....

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

FILE * ptrPerson;
FILE * ptrOutput;

struct Employe {
char prenom[20];
char nom[20];
}Names[7];

struct Employe Remplir(struct Employe Temp);
void afficher(struct Employe Temp);
void enregistrer(struct Employe Temp);
int cnt;

main()
{
printf("Le programme va maintenant lire les données contenu dans le fichier person.dat\n");
/*open file and read data*/
if ((ptrPerson=fopen("person.dat","r+b"))==NULL)
{
printf("\nErreur: le fichier n'a pu être ouvert.\n");
exit(1);
}
else
{
for(cnt=0;cnt<7;cnt++){
Names[cnt]=Remplir(Names[cnt]);
}
/* show data on screen*/
for (cnt=0;cnt<7;cnt++){
afficher(Names[cnt]);
}


}
/*Save it in oppossite order*/
if ((ptrOutput=fopen("output.dat","w+b"))==NULL)
{
printf("\nErreur: le fichier n'a pu être ouvert.\n");
exit(1);
}
else
{
for(cnt=6;cnt<=0;cnt--){
enregistrer(Names[cnt]);
}
}
fclose(ptrPerson);
fclose(ptrOutput);
return 0;
}

struct Employe Remplir(struct Employe Temp){
fscanf(ptrPerson,"%s%s\n",Temp.nom,Temp.prenom);
return(Temp);
}



void afficher(struct Employe Temp){

printf("%s %s\n",Temp.nom,Temp.prenom);
}

void enregistrer(struct Employe Temp){

fprintf(ptrOutput,"%s %s\n",Temp.nom,Temp.prenom);
}




my trouble is here:

for(cnt=6;cnt<0;cnt--){
enregistrer(Names[cnt]);
}

***********
void enregistrer(struct Employe Temp){

fprintf(ptrOutput,"%s %s\n",Temp.nom,Temp.prenom);
}


I thought it will work, but It just write nothing in my file...

any hints will be appreciated...

thanks


OH and at each function, I must warn user what the progs do..

like
printf("The progs is reading data\n");

but if I want to make the progs pause until user press a key, how do I do that....???

> any hints will be appreciated...

Use code tags for more help!!

You were testing that cnt was less than 0, but that is the stopping condition. You want to test that cnt is greater than or equal to 0.

Code:

for(cnt=6; cnt>=0; cnt--){ 
  enregistrer(Names[cnt]); 
}

>but if I want to make the progs pause until user press a key, how do I do that
Ask for input but don't assign it to anything:

Code:

puts ( "Press any key to continue" );
getchar();

-Prelude