dup the fds.  splitting the streams always leads to weirdness and pain.

would be even better if crosvm itself did logging and didn't rely on output being slurped up by someone else.

re #1: crosvm uses syslog and so doesn't rely on slurping by anybody else. A library loaded, virglrenderer in this case, uses fprintf(stderr, ...) all over the place. That's harder to fix because its part of an upstream package.

assuming crosvm (or its children) are the ones using virglrenderer, seems like something crosvm should be handling rather than vm_tools.  it can create a pipe to bind its stdout/stderr for its random libs that have poor logging semantics, and then add that fd to whatever event loop you have to convert it to syslog calls.

then there's no need for `logger`.

crosvm currently has stdout going to syslog via the logger process?  Or are there some other paths where it directly logs as well?

yes, we're using `logger` currently.  a dup of stderr to stdout would keep the status quo while also including stderr.

my suggestion was for beyond that and stop using `logger` entirely.

to be clear, i don't think it's a problem to approach this incrementally -- we're already spinning up logger and sending it output, so doing the stderr duping shouldn't be too hard.  we can then keep debating how to get rid of `logger`.