singleshell.c

/**
 * header 
 * 
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <time.h>
#include <string.h>
#define INBUF_SIZE 256

/* these should be the same as multishell.c */
#define MY_FILE_SIZE 1024
#define MY_SHARED_FILE_NAME "/sharedlogfile"

char *addr = NULL;
int fd = -1;

int initmem()
{
    fd = shm_open(MY_SHARED_FILE_NAME, O_RDWR, 0);
    if (fd < 0){
        perror("singleshell.c:fd:line31");
        exit(1);
    }
    addr = mmap(NULL, MY_FILE_SIZE,
                PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
    if (addr == NULL){
        perror("singleshell.c:mmap:");
        close(fd);
        exit(1);
    }
    return 0;
}
/**
 * todo: you can start with myshellv3.c from lecture notes
 */
int main(int argc, char *argv[])
{
    initmem();

    // Unmap the shared memory
    munmap(addr, 1024);

    // Close the shared memory file
    close(fd);
}