how to call a program in another main() function

[nanger]

I wrote a program (sim) where there is main(int argc,char *argv[]){}
this program could be executed by command line like:
sim 3
and I want to execute this command line in another main()function so as to execute this program several times in a loop
such as

for(i=0;i<5;i++)
{
  sim i;
}

how to achieve this goal?
thanks!

[z05DSL3A]

What OS are you using?
Do you want sim to run concurrently or consecutively?
...

[nanger]

linux
I have no idea about whether concurrent or consecutive, maybe the second
which one do you think could realize the loop?

THanks

[Duthomhas]

Google "concurrent" and "consecutive". You probably want the second.

This is a valid use for system().

C

#include <stdio.h>
#include <stdlib.h>
...
char cmd[10];
for(i=0;i<5;i++)
{
  sprintf( cmd, "sim %d", i );
  system(cmd);
}

C++

#include <cstdlib>
#include <sstream>
using namespace std;
...
for(i=0;i<5;i++)
{
  ostringstream cmd;
  cmd << "sim " << i;
  system(cmd.c_str());
}

Hope this helps.

[nanger]

how about my code
is there any problem with the wait() in the father process

using namespace std;
#include <unistd.h>
#include <iostream>
#include <stdio.h>
#include <sys/wait.h>

int main()
{
  pid_t pid;
  cout<<"start"<<endl;
  char str[10];
  for(int i=0;i<5;i++)
  {
  sprintf(str,"%d",i);
  pid=fork();
  switch(pid)
  {
    case -1:
            perror("fork error \n");
            exit(1);
    case 0:
            execl("/home/nanger/Desktop/try/one/sim","sim",str,NULL);
            perror("exec fail");
            exit(1);
    default:
    	    wait(NULL);
            cout<<"complete "<<i<<" times"<<endl;            
  }
  }
  return 0;
}

[Duthomhas]

That's fine.

[nanger]

thanks!