Web Development

root@meow:/var/www# ls -l /dev/ttyS0
crwxrwxrwx 1 root dialout 4, 64 Oct 28 12:47 /dev/ttyS0

root@meow:/var/www# ls -l scale
-rwxrwxrwx 1 ethan ethan 7521 Oct 28 11:11 scale

       #include <stdio.h>
       #include <fcntl.h>
       #include <sys/stat.h>
       #include <termios.h>
       #include <string.h>

        #define BAUDRATE B9600
        #define MODEMDEVICE "/dev/ttyS0"

        int main(void)
        {
            int n;
            char buff[20];

             FILE *fp1, *fp2;

            fp1 = fopen(MODEMDEVICE, "w+");

            if(fp1 == NULL)
            {
                printf("initiation error. \n");
                return 1;
            }

            fp2 = fopen("testfile.txt", "w+");

                fprintf(fp1, "%s","W\r\n");
                fread(buff,7,1, fp1);
                rewind(fp2);
                fwrite(buff, 1, 7,fp2 );
                fclose(fp2);
            
            fclose(fp1);
   }

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <stdio.h>

int main() {
        char buf[64];
        int pos=0;

        int fd=open("/dev/ttyS0", O_RDWR);
        if (fd < 0) { 
            perror("Couldn't open");
        }

        write(fd, "W\r\n", 3);

        while(read(fd, buf+pos, 1) == 1)
                if(buf[pos++] == '\n') break;

        buf[pos]='\0';

        printf("got line:\n%s", buf);
}