Copying /dev/* to another partition

Randall Tidd rtidd at mwunix.mitre.org
Thu May 31 01:09:41 AEST 1990


I am running SunOS 4.1 on a Sun 3/160.

I am trying to clone my root partition to a backup partition (just
root and subdirectories, but *not* other partitions such as /usr,
/home, etc).  I ran into a problem when trying to copy /dev; when I
try to cp /dev/sd0a (for example), it will try to read from the device
/dev/sd0a rather than copy the actual file /dev/sd0a.

I started to write a script to do it, but it was hard to parse out the
permissions; I started to write a C program to do it, but ran into
other problems:

# ls -l /dev/fd*
brw-rw-rw  2 root        16,    2 May 29 15:23 /dev/fd0
brw-rw-rw  1 root        16,    0 May 29 15:23 /dev/fd0a
brw-rw-rw  1 root        16,    1 May 29 15:23 /dev/fd0b
brw-rw-rw  2 root        16,    2 May 29 15:23 /dev/fd0c

/dev/fd0 and /dev/fd0c point to the same device (major=16 minor=2),
but one is actually a symbolic link to the other (note "number of
links" field, second field from left).  I would have to handle these
cases as well.

Rather than writing a lengthly and probably very ugly C program to do
this, is there an easier way?  I would like to keep the permisionns
and number of links intact for each file.

I tried doing a dd if=/dev/sd0a of=/dev/sd1a, but the file system got
really confused; it didn't think there was anything on /dev/sd1a, and
when I erased a couple files it said I was down to -17% capacity!

Any help would be appreciated.  Thanks in advance!

Randy Tidd
rtidd at mwunix.mitre.org
#define DISCLAIM TRUE



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