Jim Wowchuk ([log in to unmask]) wrote:
: Not knowing exactly what the person's program was doing, the suggestion for
: _exit() was more basic.  While what you say will prevent the message from
: printing twice, it can prevent it from printing at all.  Where shared
: descriptors are present from a vfork(), the exit() function in the child
: will not only flush the buffers but close the file too.  As a result, when
: the parent process attempts to print to this descriptor it will fail --
: closed file.  So instead of only one error message, it may result in none.
 
: I've been caught on this on our HP-UX systems before.! :)  I don't know the
: status of this on MPE systems.
 
The status of vfork on MPE is that there isn't one.  There is no case where
one process can close the file of another process.  Even when they share
access to the file, they each have their own file descriptors, and MPE
actually keeps track of how many times something must be closed before
its global structures go away.  What a neat idea.
 
Steve