install into fake root tree for module making

[rych]

How do the package-managers/module-makers actually make xzm modules without contaminating a live filesystem during make install?

Do they temporary change the filesystem root, i.e. something like:

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chroot /tmp/modulename make install

In my case, I'm installing an App that writes into many places in the system like /usr/share, /usr/bin, and so on. I want to collect all those writes under one subtree to make it into a module. Currently, I have to carefully examine what changed in the /mnt/live/memory/changes to find all those amendments of the new installation and copy it under /tmp/modulename, i.g., /tmp/modulename/usr/share, /tmp/modulename/usr/bin. That feels silly, there must be a cleaner way.

[ncmprhnsbl]

How do the package-managers/module-makers actually make xzm modules without contaminating a live filesystem during make install?

if it's a slackware package just:

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installpkg --root /tmp/modulename your-package.txz
or ROOT=/tmp/modulename installpkg your-package.txz

in the case of a compiler it's usually DESTDIR=
eg.

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make install DESTDIR=/tmp/modulename
or DESTDIR=/tmp/modulename ninja install

exact syntax might depend on the compiler used.
here: http://www.porteus.org/faq/desktop-faq.html#twenty9 covers this to some extent, dead links notwithstanding. also mentions changes-time to gather files installed to the live system.