I think the significant bit of information that was missing previously (the "X" in the XY Problem) is what you mentioned here: "I'm trying to create a Singularity recipes builder." By this I'm guessing you mean Singularity, and their "Recipes" to build containers, more specifically, something you can execute in their Singularity file %post section (which gets executed with /bin/sh) to build the container?

By "recipes builder", do you mean you want to write a Perl script that will generate commands that can be executed by /bin/sh to reproduce a certain environment (directory structure, links, etc.)? In other words, you want to write a Perl script that will generate a sequence of mkdir -p commands, followed by cp commands, followed by ln -s commands, such that when Singularity builds the container and executes the script containing these commands, those dirs/links/files will be present in the generated squashfs image?

(By the way, why not use the built-in %files section?)

Note that I had to deduce all this means you need to describe your task better :-) Remember to explain the "X" you're trying to accomplish, plus sample input, expected output for that input - something like a high-level SSCCE.

You haven't shown your input, which I am guessing is the filesystem that you want to mirror into the container? One way you could provide an SSCCE for us is to give us a list of commands to recreate the directory structure.

You also haven't shown your expected output, i.e. the /bin/sh script you want to produce.

Interesting: Note that both input and output are basically the same thing!

So if I'm correct with all my guesses so far, the problem can be more or less reduced to: a Perl script that will basically round-trip a /bin/sh script containing mkdir, cp, and ln commands.

However, since that's a lot of guessing, I'm going to stop here for now - please let us know if the above is correct or not, and if not, what it is you're actually trying to do. (Also, looking over choroba's sample code, it looks like a good starting point.)

In reply to Re^3: Getting all subpaths from a path by haukex
in thread Getting all subpaths from a path by ovedpo15

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