In class Shell Discussion

Objectives

Notes

  To execute   foo < file  > bar &

       < file  (part 1)
       > bar  (part 2)
       & (part 3)

First fork
   Parent
      do not do a blocking wait on the child.
   Child 
      part 1
         fd = open( file, read)
         close (STDIN_FILENO)
         dup (fd)
         close fd
      part 2
         fd = open(bar, write, ...)
         dup2(fd, STDOUT_FILENO);
         close fd
      part 4
         exec foo