directory for foreign package environment

[sagetrac-felixs]

Sometimes, foreign packages need to manipulate environment. this looks impossible right now.

It would be much better to have a directory, where packages may put environment snippets. On sage (the distribution) it makes sense to use $SAGE_ETC/env.d and set SAGE_ETC to $SAGE_LOCAL/etc.

CC: @jondo @dimpase

Component: scripts

Author: Felix Salfelder

Branch/Commit: u/felixs/env_d @ fdf7a92

Issue created by migration from https://trac.sagemath.org/ticket/15087

[sagetrac-felixs]

Branch: u/felixs/env_d

[vbraun]

comment:3

We probably want a /etc/sage/env.d directory instead of /etc/env.d if this would be installed to the fs root...

[sagetrac-felixs]

comment:4

Replying to @vbraun:

We probably want a /etc/sage/env.d directory instead of /etc/env.d if this would be installed to the fs root...

i agree that /etc/env.d does not look very useful. but first of all, packages (spkgs) are (supposedly) not required for system installation involving /etc. secondly sysconfdir (=$SAGE_ETC) should default to $prefix/etc, where $prefix should be something like /usr/local or /opt/sage (clearly not /).

standalone sagelib-into-system installations (e.g. prefix=/usr) are meant to be configured explicitly using --with-sysconfdir=/etc/sage (common practice).

i am aware that sage does not define a prefix, which makes me assume that installation is not implemented in a useful way (yet?) -- YMMV. more workarounds may be required...

[vbraun]

comment:5

Replying to @sagetrac-felixs:

sysconfdir (=$SAGE_ETC) should default to $prefix/etc, where $prefix should be something like /usr/local or /opt/sage (clearly not /).

Well /usr/local/etc/env.d doesn't sound like a particularly good place either...

[sagetrac-felixs]

comment:6

Replying to @vbraun:

Well /usr/local/etc/env.d doesn't sound like a particularly good place either...

indeed, maybe it's not a good idea to choose /usr/local as the prefix (i.e. for sage the distibution). but it's consistent.

finally it's the question how much you dislike redundant paths like $HOME/sage-xyz/etc/sage /opt/sage/etc/sage or /tmp/sage/etc/sage. i expect that /opt/sage will be the most common case for a prefix eventually, the situation looks very close to http://www.tldp.org/LDP/Linux-Filesystem-Hierarchy/html/opt.html...

[jdemeyer]

comment:7

Needs to be rebased.

[mkoeppe]

comment:11

Packages can now set environment variables by means of the spkg-configure.m4 mechanism, and old-style (out-of-tree) packages have been eliminated. So this ticket can be closed as outdated.