Probably something similar to this using lstat or stat.

knoppix@Microknoppix:~$ perl -E '
> $rdev = ( stat q{/dev/zero} )[ 6 ];
> $minor = $rdev % 256;
> $major = int( $rdev / 256 );
> say $rdev;
> say $major;
> say $minor;'
261
1
5
knoppix@Microknoppix:~$ ls -l /dev/zero
crw-rw-rw- 1 root root 1, 5 Dec  7 11:39 /dev/zero
knoppix@Microknoppix:~$ perl -E '
> $rdev = ( stat q{/dev/zram0} )[ 6 ];
> $minor = $rdev % 256;
> $major = int( $rdev / 256 );
> say $rdev;
> say $major;
> say $minor;'
64512
252
0
knoppix@Microknoppix:~$ ls -l /dev/zram0
brw-rw---- 1 root disk 252, 0 Dec  7 11:39 /dev/zram0
knoppix@Microknoppix:~$

[download]

I hope this is helpful.

Cheers,

JohnGG

In reply to Re: How do i find a file major and minor number by johngg
in thread How do i find a file major and minor number by mmw

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