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Subject: Limits to seeding /dev/random | random(4)
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When feeding /dev/random from hardware USB devices like Bill =
Woodcock=E2=80=99s design in PCB incarnation:

	https://13-37.org/de/shop/infinite-noise-trng/

Are there any caveats with regard to volume or speed of doing so ? Or is =
it always a plus ?=20

Actual code at =
https://github.com/dirkx/infnoise/blob/master/software/libinfnoise.c =
line 122:

	if ((devRandomFD =3D open("/dev/random",O_WRONLY)) <0)
		.. error handling

	if (write(devRandomFD, bytes, length) !=3D length)=20
		.. error handling

And is there any case where length would not return the length written =
=E2=80=94 it seems that the driver traps/ignores EINT, EAGAIN and short =
writes ?=20

Or should one check the entropy available in /dev/random (how?) and hold =
off feeding it until it is low enough (this is what the infinite-trng =
seems to do on linux).

With kind regards,

Dw