"/dev/dsp" is the sound interface for the OSS sound API, supported on FreeBSD
and Linux (via ALSA emulation). ioctls pass a pointer to and from the device
node. Currently strace only shows the address of the pointers, which isn't
very useful. The attached patch will trace the pointers, showing their
referenced value before and after the ioctl, expanding the masks/structs when
it could be helpful.
1. Some DSP ioctls have the same codes but different directions. dsp.c isn't
affected, but sys_ioctl (in io.c) will print both options. Not printing the
incorrect ioctl name would have required changes which would have
affected other components. This also affected the ioctl generation (some
ioctls weren't in ioctlent.h, because ioctlsort.c thought they were
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