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> Should I replace "vfork" by "fork"?  I don't have enough knowledge to
> decide.   Any OS guru?

	By no means would I consider myself an OS guru, but, this tid
bit is taken from the FreeBSD man page.  Though I haven't looked at the
code, I bet the child process isn't exiting correctly as the man page
indicates.  The use of vfork() seems like a performance win when used
correctly.  -sc

     Vfork() can be used to create new processes without fully copying the
     address space of the old process, which is horrendously inefficient inpaged environment.  It is useful when the purpose of fork(2) would have
     been to create a new system context for an execve(2).  Vfork() differs
     from fork(2) in that the child borrows the parent's memory and thread of
     control until a call to execve(2) or an exit (either by a call to
     _exit(2) or abnormally).  The parent process is suspended while the child
     is using its resources.

     Vfork() returns 0 in the child's context and (later) the pid of the child
     in the parent's context.

     Vfork() can normally be used just like fork(2).  It does not work, how-
     ever, to return while running in the childs context from the procedure
     that called vfork() since the eventual return from vfork() would then
     return to a no longer existent stack frame.  Be careful, also, to call
     _exit(2) rather than exit(3) if you can't execve(2), since exit(3) will
     flush and close standard I/O channels, and thereby mess up the parent
     processes standard I/O data structures.  (Even with fork(2) it is wrong
     to call exit(3) since buffered data would then be flushed twice.)

-- 
Sean Chittenden

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