+rule: query device inode by Major and Minor - am i inventing brand

[Arioch <the_Arioch@nm.ru>]

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Hello!

I made (and attached) a tiny rule, and hope it will be interesting to 
some of you.
See attach.
Rule is very simple ( i think someone already did that, but i'm just 
offline and cannot check it )

I made it with two thought in background:

1) Some drivers with incomplete SYSFS support (namely, wbsd on my box) 
publiches major and minor, but not the device inode name :-(
If i wantr to find it from script - how ? ls -lR | grep ?  BRR! :-) Hate 
RegExp's :-)

2) On my box pktsetup (packet-mode CD-RW burning helper, part of 
udfhelper) creates two block device per drive! I wanted to catch this.
After all it seems that it creates second inode by mknod, not kernel 
call and UDEV. But surprisingly i saw a number of other duplicate inodes 
with the identical major-minor


So, as i want to be famous, would You, please, considering including 
this rule into UDEV examples ? :-)

Ouugh, almost forgot to state a wish:
Can there be on more key for rules ?
Similar to RETURN, but matching not string form stdout, but the return 
code of program ( $? )  ?

Why - cause i wanted to do if/else/then.
I run a program to check if a symlink already exists - then i run 
another program to check if it does not exists !

And i cannot use /bin/ls or /bin/readlink and then use RESULT - it puts 
its output onto stderr if file not found, which seems to make UDEV 
ignore that rule inn the future (i could not find this in man, but i 
guess it is said somewhere on some wiki - but i'm still offline) . As 
well, stderr is not intercepted and user sees that unpretty sign of my 
sillyness :)
And i didn't want to create a separate file (bash script) for such a 
simple task.

To end this mindflow, if i mentioned man's, i'd like to say that i saw a 
typo in the "man udev".
When describing "=" operation, there is word "iNplicit" instead of 
"iMplicit". If it is not my English - it is is a typo :-)

Good luck and thank you all !

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# mailto:the_Arioch@nm.ru, xmpp:arioch@jabber.ru
#
# I want to be able to easily look for dev name by major and minor numbers
#        for example - from scripts
# So i think of having dedicated folder for symlinks to devices
#
# I should check that symlinks are not overwitten - i saw udftools' pktsetup
#   created 2 block dev-inodes per drive !
# After all, pktsetup creates its fantom by direct mknod w/o udev interaction,
#   but i found a number of other dups

# PROGRAM="/bin/sh -c ' [ -e  %r/.lookup_by_numbers/major%M@minor%m ] ' ", SYMLINK+=".lookup_by_numbers/DUP/major%M@minor%m_DUP%e"
# this rule makes easy check if any duplicate exist - dups are stored in separate dir
# enter with Midnight Commander / Nautilu / Konqueror etc - and if You can see DUP folder...

PROGRAM="/bin/sh -c ' [ -e  %r/.lookup_by_numbers/major%M@minor%m ] ' ", SYMLINK+=".lookup_by_numbers/DUP/major%M@minor%m_DUP%e"
# this rule makes easy matching - scroll through symlinks - and all DUPs and 1st link are together

PROGRAM="/bin/sh -c ' [ ! -e  %r/.lookup_by_numbers/major%M@minor%m ] ' ", SYMLINK+=".lookup_by_numbers/major%M@minor%m"