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Date: Thu, 18 Apr 1996 11:27:14 -0400 (EDT)
From: Sujal Patel <smpatel@umiacs.umd.edu>
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Subject: Changes for vfork()
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In the recent thread about rfork(), we talked about the no longer useful
vfork() syscall.  According to the manpage for vfork():

     This system call will be eliminated when proper system sharing mechanisms
     are implemented.  Users should not depend on the memory sharing semantics
     of vfork(2) as it will, in that case, be made synonymous to fork(2).

Since FreeBSD uses copy-on-write for the pages of processes that are
forked, there is little or no purpose in having the vfork() syscall (and
the man page even says it will be made synonymous to fork some day).  As
we sort of talked about, I think it's time to declare this an obsolete
syscall and perhaps move the vfork() call in libc to libcompat,
libc/compat-43, or libc/????  (I really don't know where it should go).
Also, vfork() can now just point to fork(), which will clean up some cruft
in kern_fork.c

Comments please?


Sujal