[TriLUG] cp of /dev hangs, but not tar

[Joseph Mack NA3T]

Some of my backups involve a disk-to-disk `cp -ruvp`. Some 
files in /dev (eg console, pty*) and a /var/lib/fifo I have 
cause the cp to hang. If instead I tar up that directory, it 
works fine. What's the difference between the read that cp 
does and tar does?

Most of my machines are 2.4.x. I tried a 2.6 machine

This doesn't hang
/tmp# cp -ruv /dev/console .

This hangs
/tmp# cp /dev/console .

With 2.4, both hang.

Thanks
Joe

-- 
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
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