#include<stdio.h>
#include<fcntl.h>
#include<errno.h>
extern int errno;
int main( )
{     
    // if file does not have in directory 
    // then file foo.txt is created.
    int fd = open("foo.txt", O_RDONLY | O_CREAT); 
     
    printf("fd = %d/n", fd);
     
    if (fd ==-1)
    {
        // print which type of error have in a code
        printf("Error Number % d\n", errno); 
         
        // print program detail "Success or failure"
        perror("Program");                 
    }
    return 0;
}