Re: Are there users of ash's "pathopts"? Do other shells have such a thing?

[Denys Vlasenko <dvlasenk@redhat.com>]

On 4/1/23 20:46, Denys Vlasenko wrote:
> ash allows PATH to contain "%builtin" and "DIR%func"
> pseudo-directories.
> 
> %builtin shows in what order builtins to be found
> relative to searching directories for external commands.
> 
> DIR%func allows to have a directory of "auto-loadable" functions.
> (dash git tree seems to have an example of it as src/funcs/*).


On a related note, chkmail() used to iterate over MAILPATH
using padvance(), the function which detects "pathopts".

In commit a068bf7aa310e8d36ae11c2aec47af1446a18827
"exec: Stricter pathopt parsing"
padvance() was modified, and old behavior
is retained in the form padvance_magic(..., 2),
which treats any %text as pathopt (not only %builtin and %func).

chkmail() now uses padvance_magic(..., 2) call,
presumably as exact 1:1 equivalent of old code.

But it's not necessary, right? chkmail() does not actually uses
pathopts. It can just call padvance_magic(..., 0)
so as to ignore them.

If so, then code for padvance_magic(..., 2) is unused
and can be removed. Only "magic" values of 0 and 1 will be in use.