Question

I tried two ways:

void func(const char *path, const char *arg0, ...){
        va_list args;
        va_start(args, arg0);
        execl(path, arg0, args, NULL);
        va_end(args);
}
func("/bin/ls", "ls");

And:

void func(const char *path, const char *arg0, ...){
        va_list args;
        va_start(args, arg0);
        execl(path, arg0, args);
        va_end(args);
}

func("/bin/ls", "ls", NULL);

But seems non work as expected after several test…

What’s wrong in my way of wrapping variable length parameters?

Answer 1

Since you don’t know how many arguments you’ll be receiving, you’ll need/want to use execv instead of execl. You’ll need to walk through the arguments, retrieve a pointer to the beginning of each string, and put them into an array. You’ll then pass the address of that array to execv.