On 20/01/2020 17.44, Wolfgang Denk wrote: > Dear Rasmus Villemoes, > > In message <20200108134247.31443-1-rasmus.villem...@prevas.dk> you wrote: >> The printenv command already by default hides variables beginning with >> a dot. It can be useful to take that convention even further, and >> prevent such variables from ever being stored persistently (and >> ignored if they happen to exist in stable storage). >> >> This way, one can freely use such variable names in script logic, >> without worrying about random temporary variables leaking to >> persistent storage and/or to/from another U-boot "session". > > This is not a good idea. The decision whether a variable shall be > stored permanently or not, or wheter it is readonly or writable, and > other such properties should never based on their name.
Sorry, but what other property of the variable could possibly determine those things, then? There may > be many good reasons that some .name variable _shall_ be persistent. Sure, absolutely. Which is why this is entirely opt-in for those who know they won't need that, but do have some semi-complicated script that interacts with various commands that return their output via an environment variable. > Naked-by: Wolfgang Denk <w...@denx.de> Ah, now I see how env_flags_varaccess is actually implemented, involving a .flags special variable. OK, then I can certainly see why one would not want that to be excluded from the environment - I just thought the idea behind "printenv" hiding dot-variables by default was that those were considered temporary, and not special in this way. So, would you accept introducing env_flags_varaccess_temporary, for which I could then add tmp_.*:st ? Thanks, Rasmus
