reading /dev/scd0 blocks sync(2) why ?

Harald Koenig (koenig@tat.physik.uni-tuebingen.de)
Sun, 12 Jan 1997 17:36:52 +0100 (MET)


when I'm reading data from a SCSI CDROM e.g. using

dd if=/dev/scd0 bs=2k of=/dev/null

the sync(2) system call is blocked until the "dd" command is terminated.
why ? dd opens /dev/scd0 read-only; writing to a pipe gives the same
problem so it's not writing to /dev/null...

using Linux-2.0.27, Toshiba CDROM drive connected to an AHA1542B
(only device on this SCSI bus; SCSI disks connected to NCR810).

Harald

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