nunogt · September 9, 2015 14:39 · Sep 9, 2015
diff --git a/dmesg.sh b/dmesg.sh
@@ -0,0 +1,40 @@
+#!/bin/bash
+# note: inspired by Peter
+#
+# *UPDATE 1* now we're no longer parsing ls output
+# *UPDATE 2* now we're using an array instead of the <<< operator, which on its
+# part insists on a writable /tmp directory: 
+# restricted environments with read-only access often won't allow you that
+
+# save original IFS
+OLDIFS="$IFS"
+
+for i in /sys/block/sd*; do 
+ readlink $i |
+ sed 's^\.\./devices^/sys/devices^ ;
+      s^/host[0-9]\{1,2\}/target^ ^ ;
+      s^/[0-9]\{1,2\}\(:[0-9]\)\{3\}/block/^ ^' \
+ \
+  |
+  while IFS=' ' read Path HostFull ID
+  do
+
+     # OLD line: left in for reasons of readability 
+     # IFS=: read HostMain HostMid HostSub <<< "$HostFull"
+
+     # NEW lines: will now also work without a hitch on r/o environments
+     IFS=: h=($HostFull)
+     HostMain=${h[0]}; HostMid=${h[1]}; HostSub=${h[2]}
+
+     if echo $Path | grep -q '/usb[0-9]*/'; then
+       echo "(Device $ID is not an ATA device, but a USB device [e. g. a pen drive])"
+     else
+       echo $ID: ata$(< "$Path/host$HostMain/scsi_host/host$HostMain/unique_id").$HostMid$HostSub
+     fi
+
+  done
+
+done
+
+# restore original IFS
+IFS="$OLDIFS"