Shell scripting with zsh with unknown path

Shell scripting with zsh with unknown path

[TJ Luoma]

I have always written my shell scripts in #!/bin/sh or 
#!/bin/bash but there are times when I find that I would really 
prefer to use zsh.

Ideally I'd like to be able to write all of my scripts in zsh so 
I don't have to keep two syntax/feature sets in my head.

The problem is that I don't always know where zsh will be 
installed. It could be /usr/bin/zsh or /usr/local/bin/zsh or /bin/zsh.

I have seen perl scripts which have used

     #!/usr/bin/env perl

but that did not seem to work for zsh.

TjL

Re: Shell scripting with zsh with unknown path

[Bart Schaefer]

On Jun 27, 10:56am, TJ Luoma wrote:
} Subject: Shell scripting with zsh with unknown path
}
} The problem is that I don't always know where zsh will be 
} installed. It could be /usr/bin/zsh or /usr/local/bin/zsh or /bin/zsh.

There are several options here.  Among them:

(1) Write your zsh scripts so they can be autoloaded as shell functions,
and place them in directories in your $fpath.  This doesn't work if you
want to run your zsh scripts from other shells.

(2) Use a program to fix the #! line of all your scripts whenever you
install them on a new host.  E.g.

    perl -pi.orig -e 's@^(#!)/.*?/zsh\b@$1$ENV{SHELL}@; last' ...

where "..." is some pattern that matches your script files.

} I have seen perl scripts which have used
} 
}      #!/usr/bin/env perl
} 
} but that did not seem to work for zsh.

I know others here have successfully used this, though it does cause
some complications (can't pass -f to zsh, for example).

Re: Shell scripting with zsh with unknown path

[Vincent Lefevre]

On 2011-06-27 10:56:35 -0400, TJ Luoma wrote:
> The problem is that I don't always know where zsh will be installed. It
> could be /usr/bin/zsh or /usr/local/bin/zsh or /bin/zsh.
> 
> I have seen perl scripts which have used
> 
>     #!/usr/bin/env perl
> 
> but that did not seem to work for zsh.

I use

  #!/usr/bin/env zsh

most of the time, and no problems with that. The only limitation is
that one cannot pass flags, such as -f. In such a case, one needs
something like:

#!/bin/sh

[ -n "$ZSH_VERSION" ] || exec zsh -f -- "$0" ${1+"$@"}

Now, for Emacs users, a consequence is that Emacs no longer sees it
as a zsh script. I have to put

# local variables:
# mode: sh
# eval: (sh-set-shell "zsh")
# end:

in the script. And in the .emacs:

(add-to-list 'safe-local-eval-forms '(sh-set-shell "zsh"))

If you don't have this, Emacs can add something similar for you
in your .emacs (you will have to confirm, as such eval forms can
be insecure).

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