title: how to compare two strings in system call
body: <pre><code>    #define O_WRONLY    01
      #define O_APPEND    02000
  
      int main(void)
      {
          // fd is an indentifier for the file that we are going to work with
          int fd;
          // We open the file with the write or append mode, so you will
          // have to create the file testfile.txt in the current directory.
          fd = open("jobby.txt", O_WRONLY|O_APPEND, 0);
  
  
          if(fd &lt; 0)
              return 2;
           char str[10]= "";  
        char buf1[] = "Please type username and hit Enter: ";
        write(1, buf1, sizeof(buf1));
         read (0, str, 10);
        write(fd,str, sizeof(str));
  
       char str1[10]= "";  
        char buf2[] = "Please type in a password and hit Enter: ";
        write(1, buf2, sizeof(buf2));
         read (0, str1, 10);
        write(fd,str1, sizeof(str));
  
      char str2[10]= "";  
        char buf4[] = "Please re-enter password and hit Enter: ";
        write(1, buf4, sizeof(buf4));
         read (0, str2, 10);
        write(fd,str2, sizeof(str));
  
      if(sizeof(str1)==sizeof(str2))
      {
      char buf5[] = "\n password match: ";
        write(1, buf5, sizeof(buf5)); 
      }
      else
      {
      char buf6[] = "\n password mismatch: ";
        write(1, buf6, sizeof(buf6)); 
      }
  </code></pre>
  
  <p>I wrote a system call program.I have to compare two passwords but this code is not working.How i can compare two strings? This comparing function is not working.Otherwise the code is perfect.</p>