#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <syslog.h>

/* The message to write to the terminal */
#define MESSAGE "Somethin...\n"

int main(int argc, char **argv)
{
    int fd;
    char *termfile;

    printf("Just started. I'm not a daemon yet\n");
    
    /* Remember the terminal device file we're on at this moment. */
    termfile = strdup(ttyname(1));
    if (termfile == NULL) { /* Catch just in case error. */
        fprintf(stderr, "Error: Out of memory while copying tty-name\n");
        return 1;
    }
    printf("My terminal device file is: %s\n", termfile);

    /* Daemonize */
    printf("Will try to run as a daemon now...\n");
    if (daemon(0,0) < 0) {
        perror(*argv);
        return 1;
    }
    syslog(LOG_INFO, "I'm a daemon now.");
    syslog(LOG_INFO, "I will try to write something to the terminal I was started from.");

    /* Open filedescriptor to the terminal file */
    fd = open(termfile, O_WRONLY | O_NOCTTY);
    if (fd < 0) {
        syslog(LOG_ERR, "Could not open %s. Exit..", termfile);
        return 2;
    }

    /* Write something to the terminal */
    if (write(fd, MESSAGE, strlen(MESSAGE)) < 0) {
        syslog(LOG_ERR, "Could not write to %s. Exit..", termfile);
        return 2;
    }

    syslog(LOG_INFO, "Success! I suppose the message is on the terminal now...");
    free(termfile);
    return 0;
}