[user02@FC4 Lesson04]$ cat -n cerr.c

   1  #include <stdio.h>
   2
   3  int main(void)
   4  {
   5     fprintf(stderr, "This Message Always Appears\n");
   6
   7     return 0;
   8  }

[user02@FC4 Lesson04]$ gcc -o cerr cerr.c
[user02@FC4 Lesson04]$ ./cerr
This Message Always Appears
[user02@FC4 Lesson04]$ ./cerr > test.txt
This Message Always Appears
[user02@FC4 Lesson04]$ ./cerr 2> cerr.txt
[user02@FC4 Lesson04]$ cat cerr.txt
This Message Always Appears