CODEWITHSUNDEEP
cfork
e t
e t

Reputation: 253

How to run an unlimited loop with exec without fork bombing C/unix?

char *args = "echo hello world";

while(1) {
    pid_t pid = fork()

    if(pid == 0) {
        execlp('sh', 'sh', '-c', args, (char *)NULL);
        perror("sh");
        return(1);
    } else if(pid == -1) {
        perror("fork");
        return(1);  
    }
}

I think above would fork bomb. Basically I want it to continuously print out "hello world" to stdout without it fork bombing but still usi ng fork. Is there a way? Basically to watch for a process to terminate then start a new one.

Upvotes: 0

Views: 239

Answers (1)

dbush
dbush

Reputation: 223972

The parent process can pause until the child process is finished by calling wait:

char *args = "echo hello world";

while(1) {
    pid_t pid = fork()

    if(pid == 0) {
        execlp('sh', 'sh', '-c', args, (char *)NULL);
        perror("sh");
        return(1);
    } else if(pid == -1) {
        perror("fork");
        return(1);  
    }
    // wait for the child to finish
    wait(NULL);
}

You're still looping continuously, but you're not starting a new child process until the prior one finishes.

Upvotes: 3

Related Questions