Currently a module from concurrent-output is inlined into propellor. This should be converted to a dependency. Waiting on concurrent-output reaching Debian stable. > Well, it's in stable now. Not in oldstable yet, and propellor is still > supporting the current oldstable, I believe.. --[[Joey]] [[!tag user/joey]] > This was attempted again in 2018 and had to be reverted > in [[!commit b6ac64737b59e74d4aa2d889690e8fab3772d2c6]]. > > The strange output I was seeing is the first line > of "apt-cache policy apache2" (but not subsequent lines) > and the ssh-keygen command run by `genSSHFP'` > Propellor also misbehaved in some other ways likely due to not seeing > the command output it expected. In particular Git.cloned must have > failed to see an origin url in git config output, because it nuked and > re-cloned a git repo (losing data). > > So, it seems that readProcess was somehow leaking output to the console > and also likely not providing it to the caller. > > The affected system had libghc-concurrent-output-dev 1.10.5-1 installed > from debian. That is a somewhat old version and perhaps it was buggy? > However, I have not had any luck reproducing the problem there running > readProcess in ghci. --[[Joey]] > > > Tried again in 2020, same bugs still happened. On a system running > > debian unstable with concurrent-output 1.10.9, and a system running stable that > > had cabal installed concurrent-output 1.10.11. > > > > The former system (kite) had the strange output problem. > > > > The latter system (keysafe) seemed ok but crashed at the end with > > a STM transaction deadlock. Seemed to only happen when spinning the > > host remotely, or not always; I tried to reproduce it running propellor > > manually to bisect concurrent-output but without success. > > > > This is really looking like a reversion, or several, in newer > > versions of concurrent-output. The code bundled with propellor is > > the same as concurrent-output 1.7.4. > > > I think I've fixed it, concurrent-output (>= 1.10.12 || <= 1.7.4) > > > will be needed to avoid the bug. Will be several years until that's > > > in debian stable.. > > > > > > I've updated the embedded concurrent-output copy, and it should > > > be kept up-to-date as concurrent-output changes, to avoid more > > > such reversions. --[[Joey]]