On 28/04/2021 09.14, Linus Torvalds wrote: So let me just quote that first reply of mine, because you seem to not > have seen it: > >> We have '%pD' for printing a filename. It may not be perfect (by >> default it only prints one component, you can do "%pD4" to show up to >> four components), but it should "JustWork(tm)". >> >> And if it doesn't, we should fix it. > > I really think %pD4 should be more than good enough. And I think maybe > we should make plain "%pD" mean "as much of the path that is > reasonable" rather than "as few components as possible" (ie 1). > > So I don't think "%pD" (or "%pD4") is necessarily perfect, but I think > it's even worse when people then go and do odd ad-hoc things because > of some inconvenience in our %pD implementation. > > For example, changing the default to be "show more by default" should > be as simple as something like the attached. I do think that would be > the more natural behavior for %pD - don't limit it unnecessarily by > default, but for somebody who literally just wants to see a maximum of > 2 components, using '%pD2' makes sense. > > (Similarly, changing the limit of 4 components to something slightly > bigger would be trivial) > > Hmm? > > Grepping for existing users with > > git grep '%pD[^1-4]' > > most of them would probably like a full pathname, and the odd s390 > hmcdrv_dev.c use should just be fixed (it has a hardcoded "/dev/%pD", > which seems very wrong). So the patch makes sense to me. If somebody says '%pD5', it would get capped at 4 instead of being forced down to 1. But note that while that grep only produces ~36 hits, it also affects %pd, of which there are ~200 without a 2-4 following (including some vsprintf test cases that would break). So I think one would first have to explicitly support '1', switch over some users by adding that 1 in their format string (test_vsprintf in particular), then flip the default for 'no digit following %p[dD]'. Rasmus
