How do I write and read a archive in c? - c

Question

I'm trying to write students' names and grades and read from inside the binary file, but it's not working.
I'm trying to do this without struct, because I didn't learn it yet.
Writing:
#include <stdio.h>
#include <stdlib.h>
#define Q 20
FILE *arq;
int main(int argc, char const *argv[])
{
char url[]="notas.bin";
char *dmain[Q];
arq = fopen(url,"wb");
if(arq == NULL)
{
printf("Erro, nao foi possivel abrir o arquivo\n");
exit(1);
}
for (int i = 1; i< argc; i++ )
{
dmain[i-1]=argv[i];
printf("%s\n", dmain[i-1]);
}
for (int i = 0; i < Q; i++)
{
fwrite(dmain+i, sizeof(char), 1, arq);
}
fclose(arq);
}
Reading:
#include <stdio.h>
#include <stdlib.h>
#define Q 20
#define N 10
int main (){
char url[]="notas.bin";
char *nomes[N];
int cont, nota[N], recebe[Q];
FILE *arq;
arq = fopen(url, "rb");
if(arq == NULL)
{
printf("Erro, nao foi possivel abrir o arquivo\n");
exit(1);
}
cont = fread(recebe, sizeof(char), Q, arq);
if (cont !=Q)
fprintf (stderr, "Foram lidos apenas %d Elementos!!!\n" , cont) ;
/* Apresentar os dados ao usuário */
for (int i=0; i<Q; i++)
printf ("%d N: %d \n", i+1, recebe[i]);
fclose(arq);
}
This is still the prototype, I was writing and the reading is kind of sus with numbers repeating:
Sending the data:
PS C:\\Users\\gabri\\OneDrive\\Documentos\\GitHub\\Programacao1\\Exercicio 7\> & ."prog4_escrever_arquivo_bin_notas.exe" gabriel 90 pedro 80 sandra 70 brenda 80 tiago 60 barbara 60 maria 90 ana 60 vitor 90 caze 70
gabriel
90
pedro
80
sandra
70
brenda
80
tiago
60
barbara
60
maria
90
ana
60
vitor
90
caze
70
Reading the data:
PS C:\\Users\\gabri\\OneDrive\\Documentos\\GitHub\\Programacao1\\Exercicio 7\> & ."prog5_ler_arquivo_bin_notas.exe"
1 N: 1614815232
2 N: -524246912
3 N: 1614815232
4 N: -524246912
5 N: -533675952
6 N: 654
7 N: -151458356
8 N: 32763
9 N: 2
10 N: 654
11 N: 0
12 N: 0
13 N: 974291712
14 N: 654
15 N: 268501009
16 N: 227
17 N: 976422744
18 N: 654
19 N: -151528186
20 N: 32763