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Bug#267142: huh?



On Fri, Sep 10, 2004 at 09:49:34PM -0700, Thomas Bushnell BSG wrote:
> But my first reaction to the issue here is to simply depend on bash.
> If I were to fix the bug in question, I would not alter my use of test
> to comply with some foolish idea about what "looks better".  To me, -a
> looks better, because -a is typical for command arguments and "&&" is
> not.  "&&" looks like a freaky backgrounding command to me.  And in
> Version 7 Unix, -a was the only option, so it's really "&&" that is
> the freaky novelty.  To my eye, at least.

&& was perfectly well-supported in the v7 Unix shell. Of course it isn't
typical for command arguments; that's because it isn't a command
argument, but an operator for joining two pipelines together.

  $ unix-v7
  
  PDP-11 simulator V3.2-2
  Disabling XQ
  @boot
  New Boot, known devices are hp ht rk rl rp tm vt
  : rl(0,0)rl2unix
  mem = 177856
  # test -d bin; echo $?
  0
  # test -d nonexistent; echo $?
  1
  # test -d usr; echo $?
  0
  # test -d bin -a -d usr; echo $?
  0
  # test -d bin && test -d usr; echo $?
  0
  # test -d bin -a -d nonexistent; echo $?
  1
  # test -d bin && test -d nonexistent; echo $?
  1
  #

The Autoconf manual refers (Portable Shell / Limitations of Builtins) to
precedence problems on System V as the rationale for avoiding -a and -o.
I don't see how you can logically use the behaviour of Version 7 Unix as
justification for anything while overlooking System V.

Cheers,

-- 
Colin Watson                                       [cjwatson@debian.org]



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