Zsh option for checking if a file is a shell script

Zsh option for checking if a file is a shell script

[Guillaume Brunerie]

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Hi,
Is there some option (for example --check-syntax) such that
$ zsh --check-syntax /path/to/a/shell/script
doesn’t do anything except that the return code would be 0
if /path/to/a/shell/script is indeed a shell script, and non zero otherwise?
(in particular I don’t want to execute the shell script at all)
I want to know if a given file is a shell script or not, and I cannot use
the extension or the shebang because some files (e.g. /etc/zprofile) doesn’t
have any of them.

Thank you.

Guillaume Brunerie

Re: Zsh option for checking if a file is a shell script

[Bart Schaefer]

On Aug 12, 12:23pm, Guillaume Brunerie wrote:
}
} Is there some option (for example --check-syntax) such that
} $ zsh --check-syntax /path/to/a/shell/script
} doesn't do anything except that the return code would be 0
} if /path/to/a/shell/script is indeed a shell script, and non zero otherwise?

$ zsh -n /path/to/some/file

or equivalently but more obviously

$ zsh -o no_exec /path/to/some/file

will parse but not execute the file, and exit with failure if there is
a parse error.  However, just because a file doesn't cause a parse error
is not a guarantee that it is a shell script, and parsing a very big
file is potentially expensive.

Re: Zsh option for checking if a file is a shell script

[Guillaume Brunerie]

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2010/8/12 Bart Schaefer <schaefer@brasslantern.com>

> On Aug 12, 12:23pm, Guillaume Brunerie wrote:
> }
> } Is there some option (for example --check-syntax) such that
> } $ zsh --check-syntax /path/to/a/shell/script
> } doesn't do anything except that the return code would be 0
> } if /path/to/a/shell/script is indeed a shell script, and non zero
> otherwise?
>
> $ zsh -n /path/to/some/file
>
> or equivalently but more obviously
>
> $ zsh -o no_exec /path/to/some/file

will parse but not execute the file, and exit with failure if there is
> a parse error.


Thank you :-)


> However, just because a file doesn't cause a parse error
> is not a guarantee that it is a shell script, and parsing a very big
> file is potentially expensive.
>

I want that because I have aliased cat to use 'source-highlight' when given
only one argument (in order to have syntax highlighting in the shell) and
this doesn't work for shell scripts without extension nor shebang (like most
system scripts in /etc).
But it seems indeed that many files are syntactically correct but aren't at
all shell scripts (like /etc/inittab).
If someone knows a better solution, please let me know.