This is intentional, more or less. The -D logfile is for the debug logs enabled with -d, not for strace. I think if we wanted to support redirecting strace output to a file we might need to have an extra argument, to avoid breaking existing users.
-- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1748612 Title: qemu-user option -strace -D <file> doesn't work Status in QEMU: New Bug description: I have been trying to access qemu -strace output from a script The main problem was it was on stderr, the strace output was merged with my program's stderr output. Then I tried to use the -D option, to log the output to a file. This didn't work even if the log file was created, but it was empty. I have looked at the source code and found the print function was not qemu_log with -strace but gemu_log (to be clear it was GEMU NOT QEMU) I have then replaced all gemu_log by qemu_log removed declaration of gemu_log and recompiled, it seems to works just fine right now. removed declaration here and here: https://github.com/qemu/qemu/blob/master/linux-user/main.c#L108 https://github.com/qemu/qemu/blob/master/linux-user/qemu.h#L203 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1748612/+subscriptions
