I am attempting to adjust brightness via '/proc/acpi/ibm/brightness', but I get permission denied if I do it via sudo -- I have to su to root in order to do the adjustments. Log at [1].
[1] bry...@esterhazy:~$ sudo echo up > /proc/acpi/ibm/brightness bash: /proc/acpi/ibm/brightness: Permission denied bry...@esterhazy:~$ su Password: esterhazy:/home/bryans# echo up > /proc/acpi/ibm/brightness /* Display brightness increases */ [end 1] I am in my /etc/sudoers file with all permissions. My /etc/sudoers file, with comments stripped, is at [2]. [2] Defaults env_reset root ALL=(ALL) ALL bryans ALL=(ALL) ALL [end 2] My sudoers seems alright as I can execute other privileged commands with no difficulty, just not mess around with the files in /proc (those few I've tried) I don't think it _can_ be a permissions issue, as by my understanding, absolutely no permission checks are applied to root by userspace -- though correct me if I'm wrong. I tried to "sudo echo h > /proc/sysrq-trigger", and again was denied. This led me to look in "$linux/kernel/sysrq.c", but I found nothing useful in determining why I can't do this using sudo. I'm left to several possibilities: 1. I'm misunderstanding some documentation somewhere (PEBKAC) 2. sudo cannot allow me to do this, possibly due to restrictions elsewhere in the kernel [3] 3. I'm able to do this, but I'm just not looking in the right place for how to enable it [3] Highly unlikely, by my knowledge. -- _ ASCII Ribbon Campaign Against ( ) Brian Ryans HTML E-mail and V-cards X brianlry...@gmail.com www.asciiribbon.org / \ GPG Public Key 0xC11213D0 Key Fingerprint: 8B2A 54C4 E275 8CFD 8A7D 5D0B 0AD0 B014 C112 13D0
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