fork() undeclared error

Question

I need to be able to use fork() for a small project. The thing is that the example code is not working:

#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>

int main()
{ 
    pid_t pID = fork();
    if (pID == 0) // child
    {
        printf("CHILD\n");
        // Code only executed by child process
    }
    else if (pID < 0) // failed to fork
    {
        printf("FAIL\n");
    }
    else // parent
    {
        printf("PARENT\n"); // Code only executed by parent process
    }
    // Code executed by both parent and child.

    system("PAUSE");
    return 0;   
}

The compiler says: "20 D:\Untitled1.cpp `fork' undeclared (first use this function)"

But I have read in the internet that it should be located in #include <unistd.h>.

Any ideas? Thanks!

IIRC, Windows does not have `fork()`. It *is* in `unistd.h` on *POSIX* systems. (Windows is not 100% POSIX-compliant.) — cdhowie, Mar 21 '13 at 18:04
Well that was fast, do you know any other function I could use that does the same thing? Thanks! — Oliver Hoffman, Mar 21 '13 at 18:05
See [this question](http://stackoverflow.com/q/985281/501250). If you are wanting a POSIX-like fork, then using Cygwin is probably your best option. — cdhowie, Mar 21 '13 at 18:06

score 6 · Accepted Answer · edited Mar 21 '13 at 18:16

6

On Windows you can't use fork(). Use CreateProcess()/CreateProcessEx() instead.

edited Mar 21 '13 at 18:16

Grijesh Chauhan

55,177
19
133
197

answered Mar 21 '13 at 18:06

Mayhem

386
1
10

Thank you! I will look into it. – Oliver Hoffman Mar 21 '13 at 18:09
4

CreateProcess is equivalen to fork()+exec() combo, not fork() alone. – el.pescado - нет войне Mar 21 '13 at 18:16

fork() undeclared error

1 Answers1