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#include "rc.h"
#include "parse.h"
#include "exec.h"

#include <signal.h>
#include <termios.h>

// -----------------------------------------------------------------------
// globals

Thread *runner = nil;
Shell shell    = { 0 };

// -----------------------------------------------------------------------
// functions

void
initshell(void)
{
    if((shell.interactive=isatty(0))){
        while(tcgetpgrp(0) != (shell.pid = getpgrp()))
            kill(-shell.pid, SIGTTIN);

        /* ignore job control signals */
        signal(SIGINT,  SIG_IGN);
        signal(SIGQUIT, SIG_IGN);
        signal(SIGTSTP, SIG_IGN);
        signal(SIGTTIN, SIG_IGN);
        signal(SIGTTOU, SIG_IGN);
        /* 
         * NOTE: if SIGCHLD is set to SIG_IGN then
         *  1. children that terminate do not become zombies
         *  2. call a to wait() will block until all children have terminated
         *  3. the call to wait will fail with errno == ECHILD
         *  see for discussion:
         *      https://stackoverflow.com/questions/1608017/no-child-process-error-from-waitpid-when-waiting-for-process-group 
         */
        // signal(SIGCHLD, SIG_IGN);

        /* take control */
        shell.pid = getpid();
        if(setpgid(shell.pid, shell.pid)<0)
            fatal("could not put shell in its own process group");

        tcsetpgrp(shell.pid, shell.pid);
    }
}

// -----------------------------------------------------------------------
// main point of entry

int
main(int argc, char *argv[])
{
    shell.err = openfd(2);

    initenv();
    initpath();
    initkeywords();
    initshell();
    inithistory();

    enablevi();
    xboot(argc, argv);
    /* unreachable */
}