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   Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 21:38:31 JST Jan Wildeboer 😷:krulorange:

   #lazyweb Weird thing. When using `sed` in a makefile context, its seems to behave slightly different than expected, as explained in [1]. More precise: To capture the end of a line, you normally use $ as the last character in the search expression, but in a makefile context it somehow needs $$. The linked post explains *THAT* it works this way but not *WHY*. This upsets me ;) Can anyone explain what is going on here?

   [1] https://stackoverflow.com/questions/57301214/why-using-two-dollar-sign-instead-of-just-single-dollar-sign-for-bl

   • Embed this notice
     Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 21:48:18 JST Jan Wildeboer 😷:krulorange:

     in reply to

     • thp

     @thp Hrmbl. I'll try to add that weirdness to my brain in the hope it can recall it when needed.Thank you for the through explanation!

   • Embed this notice
     thp (thp@dosgame.club)'s status on Sunday, 19-Jan-2025 21:48:20 JST thp

     in reply to

     @jwildeboer The backslash is interpreted by the shell, the single "$" is interpreted (consumed) by make, as it tries to access a variable $" (dollar-sign, followed by double-quote). To echo a "$", you need to:

     1. Escape using "\" for the shell
     2. Escape using "$$" for make

     Note how the make output of the first file is just the line:

     echo "\

     And the second invocation gets it as:

     echo "\$"

   • Embed this notice
     thp (thp@dosgame.club)'s status on Sunday, 19-Jan-2025 21:48:21 JST thp

     in reply to

     @jwildeboer Make treats "$" as special character. $$ escapes it, so that the shell sees just a "$".

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     Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 21:56:11 JST Jan Wildeboer 😷:krulorange:

     in reply to

     • thp

     @thp (also, #mastodon, markdown for code blocks in toots, when? ;)

   • Embed this notice
     Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 22:07:50 JST Jan Wildeboer 😷:krulorange:

     in reply to

     • Joost van Baal-Ilić

     @joostvb Got that (and actually knew that, but is was deeply buried in my brain) I just missed the mental connection as I saw this syntax in a docker compose file :)

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     Joost van Baal-Ilić (joostvb@mastodon.green)'s status on Sunday, 19-Jan-2025 22:07:52 JST Joost van Baal-Ilić

     in reply to

     @jwildeboer you have to escape a $ in make since it's a special character to make.

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     Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 22:10:18 JST Jan Wildeboer 😷:krulorange:

     in reply to

     Thank you for the replies and explanations! Variable expansion in makefiles is the answer. Why I saw that syntax in a docker compose file is now the next question. I *guess* because it does a similar thing wrt variable expansion before handing the sed command to be executed, but I am not that much of a docker expert.

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     Jan Wildeboer 😷:krulorange: (jwildeboer@social.wildeboer.net)'s status on Sunday, 19-Jan-2025 22:42:47 JST Jan Wildeboer 😷:krulorange:

     in reply to

     • Wusel

     @mrwslpro Yep. That thread occupied my brain and disturbed my sleep, so I needed to dive deeper :)

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     Wusel (mrwslpro@procial.tchncs.de)'s status on Sunday, 19-Jan-2025 22:42:49 JST Wusel

     in reply to

     @jwildeboer@social.wildeboer.net this question felt like a deja vu. And it kind of was: reading the question in forgejo's chat ha