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Comment by divbzero | Hacker News Reader

I bet many of us do this due to small differences between BSD and GNU coreutils. One that always gets me is:

  sed -i '' 's/foo/bar/g'  # BSD sed
  sed -i 's/foo/bar/g'     # GNU sed

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That is indeed an incredibly frustrating difference, because there is no version of it that works on both GNU and macOS. In practice I often end up using perl to do an in-place search-replace instead.

It takes a second to install gnu coreutils with homebrew and make Macs barely useable

Or just use Perl

As long as you're using stone knives, might as well throw in some bear skins.

https://www.youtube.com/watch?v=F226oWBHvvI

Fun! But honestly there's a place for Perl.

There's far less variance between Perls on different systems than there are for sed/awk/shell. So if you want performant portable code, Perl does better than all of those.

I'd never use Perl for a 'big' program these days but it still beats the crap out of the mess of sed/awk/bash/ksh/zsh.

Apple has been threatening to remove perl for ages. One of these days they'll find the "courage" to do so and we'll need a better strategy.

FreeBSD removed Perl from base ages ago, in FreeBSD 5 or 6. That went alright.

I don't even have it on my Linux system any more; for better or worse, fewer and fewer things use it.

I much prefer Linux but having used Macs a few times for work, I absolutely cannot recommend making GNU coreutils the default option on Macs.

If you make GNU coreutils the first binaries in PATH, you can expect subtle, _very nasty_ issues.

The last one I encountered was `hostname` taking something like 5 seconds to run. Before that, there was some bug with GNU’s stty which I don’t remember the specifics of.

But "sed -i'' s/../../ FILE" will work on both, no? Or -i.orig if you want to keep a backup file?

That does not work on macOS. "-i''" is the same as just a bare "-i", and it will then interpret the next argument as the backup suffix.

Oops yes, that should have been -i '' with a space. But I see now that GNU doesn't accept -i '', or even -i .orig. It MUST be without a space: "-i.orig". The reason for that I assume is there's no way to disambiguate:

  echo foo | sed -i pattern
  echo foo | sed -i .orig

But you can still use "-i.orig"; that should work on both. That will leave you with a .orig file to clean up, but arguably that's not a bad thing as -i can clobber files.

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