Program with named pipes sometimes working sometimes fails - c

Question

Hello I am trying to do a program in c that uses named pipes to communicate with another program but if i run it more than once it fails most of the time with occasionally working perfectly, even though i don't change anything between tests.
Here is the code for arbitro.c the program that i execute first
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
int main(int argc, char *argv[])
{
int fd,id1,cont_pront=0,i=0;
char nomejog[40]="",instrucao[40]="";
// FIFO file path
char * myfifo = "myfifo";
// Creating the named file(FIFO)
mkfifo(myfifo, 0666);
do{
fd = open(myfifo,O_RDONLY);
if(fd == -1){
fprintf(stdout, "Erro a abrir.\n");
}
// First open in read only and read
for(int i=0;i<2;i++){
read(fd, nomejog, 40); //Recebe o nome do jogador
read(fd, &id1,sizeof(id1)); //Recebe o id do primeiro jogador
fprintf(stdout, "Nome: %s -» %d\n", nomejog,id1);
cont_pront++;
}
fprintf(stdout, "Nº: %d\n", cont_pront);
//Now open in write mode and write
fd = open(myfifo,O_WRONLY);
if(fd == -1){
fprintf(stdout, "Erro a abrir.\n");
}
if(cont_pront >= 2){
cont_pront = -1;
}
write(fd, &cont_pront, sizeof(int));
close(fd);
// optind is for the extra arguments
// which are not parsed
for(; optind < argc; optind++){
if(i == 0){
printf("Duração do campeonato: %s\n", argv[optind]);
}else{
if(i == 1){
printf("Tempo de espera: %s\n", argv[optind]);
}
}
i++;
}
}while(strcmp(instrucao,"exit") != 0);
return 0;
}
and here is the code for cliente.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
int main(int argc, char *argv[]){
int fd1,cont_pront=0;
char nomejog[40]="";
// FIFO file path
char * myfifo = "myfifo";
// Creating the named file(FIFO)
mkfifo(myfifo, 0666);
// Open FIFO for write only
fd1 = open(myfifo, O_WRONLY);
//Enviar o nome do jogador ao arbitro
for(int i=0;i<2;i++){
write(fd1, nomejog,strlen(nomejog)+1); //Envia o nome do jogador já pronto
write(fd1,&i, sizeof(int)); //Envia o id
strcpy(nomejog,"pedro");
}
close(fd1);
//Receber quantos jogadores estão prontos
fd1 = open(myfifo, O_RDONLY);
read(fd1, &cont_pront, sizeof(int)); //Recebe o nome do jogador
if(cont_pront == -1){
//Tem jogadores necessários para começar o jogo
fprintf(stdout,"Existem jogadores suficientes, o campeonato vai ser iniciado...\n");
execl("GAMEDIR/game01","GAMEDIR/game01", NULL);
}else{
//Ainda não tem jogadores suficientes para começar o jogo
fprintf(stdout,"Nao tem jogadores suficientes para comecar o campeonato.\n");
}
close(fd1);
return 0;
}
if everything goes well this is supposed to say that there are enough players and the executes the game, but for some reason sometimes it repeats everything sending more players in blank or the client stops midway execution or even doesn't send the correct players in the first place