Re: Parallelization of shell scripts for 'configure' etc.

[Bob Friesenhahn]

On Thu, 16 Jun 2022, Demi Marie Obenour wrote:
> Finally, a small but probably noticable improvement would come
> from dropping support for ancient platforms, such as Ultrix.  A much
> bigger win would be to use Bash or Zsh if they are installed, as that
> allows using modern shell tricks (such as [[ "$a" =~ [0-9]+ ]] and
> "${a//a/b}") that do not require forking new processes.

The configure script already tries to deduce the best shell 
(CONFIG_SHELL) to use to run the rest of the configure script.  It is 
pretty common that the shell selected is bash (if it was not already 
bash).

It has been noticed that bash is rarely the fastest shell out of the 
options available.  For example 'dash' is often used since it tends to 
execute more quickly.

If projects established a baseline for the antiquity of the targets 
they support, then the number of tests can be reduced and configure 
will run faster.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
Public Key,     http://www.simplesystems.org/users/bfriesen/public-key.txt