tcsh -X behavior

tcsh -X behavior

[Vincent Lefevre]

Could we have the tcsh -X behavior in zsh conditional expressions?

The tcsh manual says:

         X   Executable in the path or shell builtin, e.g.  ` - X
             ls'  and  ` - X  ls - F' are generally true, but `-X
             /bin/ls' is not (+)

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/> - 100%
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Work: CR INRIA - computer arithmetic / PolKA research team at LORIA

Re: tcsh -X behavior

[Nemeth Ervin]

Vincent Lefevre <vincent@vinc17.org> writes:

> Could we have the tcsh -X behavior in zsh conditional expressions?
> 
> The tcsh manual says:
> 
>          X   Executable in the path or shell builtin, e.g.  ` - X
>              ls'  and  ` - X  ls - F' are generally true, but `-X
>              /bin/ls' is not (+)

You want probably the hash builtin:

     hash [ -dfmr ] [ name[=value] ] ...

[snip...]

          value.  For each  name  with  no  corresponding  value,
          search  for name in the path, and add it to the command
          hash table, and  associating  it  with  the  discovered
          path, if it is found.

So in a shell-script:

if hash ls 2> /dev/null; then
        :
fi

-- 
Ervin
						"Intelligenti pauca."

Re: tcsh -X behavior

[Vincent Lefevre]

On Fri, Oct 13, 2000 at 18:08:25 +0200, Nemeth Ervin wrote:
> So in a shell-script:
> 
> if hash ls 2> /dev/null; then
>         :
> fi

I currently use "whence >/dev/null" (it checks for aliases too, but this
is OK for me). What is the best one?

But IMHO, a -X operator would be a good idea.

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/> - 100%
validated HTML - Acorn Risc PC, Yellow Pig 17, Championnat International des
Jeux Mathématiques et Logiques, TETRHEX, etc.
Work: CR INRIA - computer arithmetic / PolKA research team at LORIA