Re: parallel and Mac

[Ernst, Kevin]

On 7/26/24 at 1:11 PM, Alan wrote:
> What is the right way to get GNU parallel running on a Mac?

Installing GNU Parallel from the release tarball at 
https://www.gnu.org/software/parallel should theoretically work fine, 
requiring only built-in software that comes with macOS.

I am not too sure about _very_ recent macOS releases, though, as things 
_do_ get removed from the base OS as time goes on[0]. Also not sure if 
newer macOS includes a C compiler without installing Xcode, running 
'xcode-select --install', or downloading the command-line tools from 
their developer site[1], which requires an account. Such is life when 
you stray from the beaten path in macOS.

Both the GNU Parallel tutorial[2] and the README included in the tarball 
should have instructions for performing the install. This will go into 
/usr/local/bin, which appears to be in the default search path for 
macOS. I tried myself on an older-but-supported macOS release with $PATH 
set to /usr/bin:/bin:/usr/sbin:/sbin only (excluding any software I had 
installed myself or via MacPorts) and it worked fine.

What _you_ have at present is 'parallel' from moreutils[3], which 
provides several _other_ useful utilities, among them 'pee', 'vidir', 
and 'sponge'.

So getting the two 'parallel's confused is a very relatable situation. 
vDebian-based Linux distributions have a workaround, and that is to move 
'parallel' from moreutils to 'parallel_moreutils' so that you can have 
both packages installed. However, based on [4] from the Homebrew web 
site, I don't know if there's such an option with Homebrew.

If you don't have any luck with installation from source, as described 
above, and you're sure you don't need any of the utilities provided by 
'moreutils', you could uninstall 'moreutils', and then 'brew install 
parallel' to get GNU Parallel. I'm not sure Ole considers Homebrew a 
"supported" platform, though, so if you have problems with the version 
in Homebrew, it's probably best to report problems through that 
project's particular support channels.

Hope that helps.

--Kevin


[0]: 
https://developer.apple.com/documentation/macos-release-notes/macos-catalina-10_15-release-notes#Scripting-Language-Runtimes
[1]: https://developer.apple.com/xcode/resources
[2]: 
https://www.gnu.org/software/parallel/parallel_tutorial.html#prerequisites
[3]: https://joeyh.name/code/moreutils
[4]: https://formulae.brew.sh/formula/parallel