[uClinux-dev] msh: detect if a file exists

[Michael Schnell]

> I did "man sh", "man test" or "man [" - all of them (on Ubuntu) have
> -e but not -a for file testing. :-)
>   
I did man bash on Suse 10.3
> There's no msh documentation as far as I know, but it's basically a
> standardish old-style Bourne shell with some bugs, and notably no
> user-defined functions (which are a modern feature anyway).  So most
> "sh" documentation applies to msh.
>   
> Bash is full of extensions to the Bourne shell, so a lot of what you
> see in the Bash documentation does not apply to msh.
>   
I'm aware of that.
> On some Linuxes "man sh" gives you Bash documentation; on others, it
> gives you Ash documentation which is closer to old-style Bourne shell.
>   
I did not know that there in fact is a "sh". I thought sh would be 
always used as a symlink to the best shell on the system so that this is 
used. On my Suse sh is a symlink to bash, on my uCLinux by default it's 
a symlink to sash,.

But "man sh" in fact shows an appropriate documentation that seems to be 
usable for msh (but here I don't fined the -e in the "man sh" file. 
Neither in "man [" :(  ).

> Having said all that, in your problem it's not the msh command at all.
> If you study Bourne shell, you'll see the command is "if COMMAND; then
> ...".
>
> So you are running the command "[ -e file ]".  That means you need the
> documentation for the "[" command - there really is one :-)
>   
OK, but without documentation it's really hard "man [" see above and "[ 
--help" does nothing useful " in my system.
> It's the same as the "test" command.  It happens to be built in to
> some shells, including Bash, but not all.
Ahhhh ! (Though [ additionally seems to search for a "]" . )

"test --help" does nothing, but "man test" provides the information you 
gave me; no -a, but -e is described :).

Thanks again !
-Michael