[gobolinux-users] Program dependency registering among each other

[Jan Molič]

Hello,

sometimes when you install new library and then remove old, some programs 
don't start, because depend on the old library.

If it happen to programs like KDE, it's very confusing to find out which 
library cause problems, especially if you upgrade more libraries at once.

My solution would be to register each program to another's Resources/UsedBy. 
For example if we have four versions of libA,

libA/1.0
libA/2.0
libA/3.0
libA/4.0

then install programB/1.1 which depends on libA >= 2.0 and libA <= 3.0, 
programB will be symlinked to

libA/2.0/Resources/UsedBy/programB--1.1
libA/3.0/Resources/UsedBy/programB--1.1

If you want to remove libA/2.0, RemoveProgram firstly check which program 
depends on libA/2.0. If it found another version covering programB/1.1 
dependency, libA would be removed. Otherwise RemoveProgram would complain. If 
you remove programB/1.1, the UsedBy link will break and will be considered as 
not there.

Jan