[U-Boot-Users] simplify bootm command

[Wolfgang Denk <wd@denx.de>]

In message <48982DAD.2060408@gmail.com> you wrote:
>
> That would be REALLY cool!  It would take some initial work, but the 
> reward would be really simple and transparent expandability for the 
> command set.  As with the "bootm" command, we might end up with simpler 
> code (I don't think too many commands are as bad as bootm, however).

:-)

> One minor flaw, I don't see how "bootm" the env script could run "bootm" 
> the built-in command, because it would instead recursively run "bootm" 
> the env script if scripts have higher priority and the command line 
> "bootm" would run the built-in "bootm" if scripts have lower priority. 

That's why I think we should have an explicit "builtin" command, i. e.
command with the name "builtin" that will always run the corresponding
builtin command, no if there is a "command alias" or not - similar to
the bash command:

       builtin shell-builtin [arguments]
              Execute the specified shell builtin, passing it
              arguments, and return its exit status. This is useful
              when defining a function whose name is the same as a
              shell builtin, retaining the functionality of the
              builtin within the function. The cd builtin is commonly
              redefined this way. The return status is false if
              shell-builtin is not a shell builtin command.

> The way I see it, env scripts should have higher priority than built-in 
> commands and would supercede the built-in.  Hmm, one possible way out of 
> the dilemma would be to support quoting built-in commands to force them, 
> rather than the env script: `bootm` would be the built-in command (just 
> as a concept, I don't know how back-tick quoting would conflict with 
> existing hush parsing).

I don't like to use quoting (of  any  kind)  for  this  because  this
already  has  certain  meaning in the shell. Also, this would be more
effort to implement that the "builtin" command I suggested.

Best regards,

Wolfgang Denk

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