David Korn wrote:
> Subject: Re: [ksh93-integration-discuss] [Bug 399] New: "alias.sh" may
> execute the wrong command
> --------
> > > ... if PATH is /usr/xpg4/bin:/usr/bin, a "ls" builtin is bound to
> > > /usr/bin/ls
> > > and the script should execute the "ls" builtin it will execute
> > > /usr/xpg4/bin/ls
> > > instead of the builtin command because /usr/xpg4/bin comes before
> > > /usr/bin in
> > > PATH.
>
> I must be missing something. If ls is a builtin for /usr/bin/ls
> but /usr/xpg4/bin comes before /usr/bin in PATH, then ls should run
> /usr/xpg4/bin/ls, not the built-in version of /usr/bin/ls.
>
> That is the whole point of binding a builtin to a path name rather than
> just making ls a builtin.
Erm... yes... but in this case it's a bit different: Assume /usr/bin/ls
is a ksh93 shell script which calls a ksh93 builtin called "ls" (which
is bound to /usr/bin/ls) like this:
-- snip --
#!/usr/bin/ksh93
ls "$@"
-- snip --
In this case the call to "ls" will walk all elements in ${PATH} and
check whether there is a "ls" command. If any path element before
/usr/bin/ contains an command called "ls" then this script (itself being
the _file_ called /usr/bin/ls) will execute that command instead of the
(intended) builtin bound to /usr/bin/ls ... ;-/
Originally I thought that I can just place a $ export PATH=/usr/bin # at
the top of the script to get rid of the issue... but then I realised
that this will break the "type" builtin (which is available as a shell
script called /usr/bin/type in Solaris).
----
Bye,
Roland
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