Re: /dev/fd/62: No such file or directory

[Greg Wooledge]

On Fri, Mar 28, 2014 at 08:21:40AM -0700, Linda Walsh wrote:
>       What I'd prefer to see is that bash do what you say at
> runtime, rather being limited to that choice at build time.

If you require process substitution features in a script that may be
executed when the OS is not fully booted, I'd say you should explicitly
used a named pipe instead.  An alternative would be to use a
specially-built bash in the boot environment, which uses the named pipe
implementation internally.

> Isn't it only things that are like "read xxx < <(cmd)" ? or is there
> something else that uses  process substitution??

My guess would be that < <(cmd) on a read or a while loop is the most
common use of process substitutions.  I sometimes see diff <(cmd1) <(cmd2).
The >(cmd) form seems to be much less common, mostly used for logging
a whole script through a filtering command (or simply tee).

I don't think I've ever seen a boot script use process substitutions,
but I admit I haven't studied a lot of them.  Mostly the ones I've seen
are written for /bin/sh = dash (or ksh or Bourne shell) anyway.