kern/65786: [vfs_syscalls.c] Incorrect fifo semantics

[Robert Watson]

Synopsis: [vfs_syscalls.c] Incorrect fifo semantics

State-Changed-From-To: open->patched
State-Changed-By: rwatson
State-Changed-When: Tue Sep 13 11:24:53 GMT 2005
State-Changed-Why: 
I independently bumped into this bug while investigating a race condition
in fifos, and drew the same conclusion as Bruce: POSIX specifies that
ESPIPE should be returned on lseek() attempts.  This has been patched as
fifofs_vnops.c:1.119 in 7.x-CURRENT, and will be merged to other branches
after additional testing time has passed.  The commit information:

  revision 1.119
  date: 2005/09/12 12:15:12;  author: rwatson;  state: Exp;  lines: +1 -1
  Remove DFLAG_SEEKABLE from fifo file descriptors: fifos are not seekable
  according to POSIX, not to mention the fact that it doesn't make sense
  (and hence isn't really implemented).  This causes the fifo_misc
  regression test to succeed.

I'm leaving this PR in the patched state until the fix is merged to
appropriate branches.


http://www.freebsd.org/cgi/query-pr.cgi?pr=65786