[mythtv-users] External Channel Change Question? - WAS Re: CentOS and MythTV

[Kenneth Hadley]

Len Reed wrote:
> Kenneth Hadley wrote:
>   
>> Brian Wood wrote:
>>     
>>> On Feb 12, 2006, at 7:02 PM, Kenneth Hadley wrote:
>>>       
>>>> Appears I spoke too soon about have no further problems.
>>>>
>>>> I use a MyBlaster to control my external Samsung DirecTV receiver and
>>>> with my previous box this worked fine using the MyBlaster.pl script.
>>>>
>>>> This time...not working so well.
>>>>
>>>> I have the script located in /usr/local/bin/ and typed into the input
>>>> field of "mythtvsetup=>input connections=>/dev/video0/=>External  
>>>> channel
>>>> change command" the script path/filename (/usr/local/bin/MyBlaster.pl)
>>>> but when I record programs the channel never changes and when watching
>>>> the MyBlaster transmitter when the recording starts and it should be
>>>> blinking, it does not.
>>>>
>>>> Manually typing at the CLI
>>>> [mythtv at pvr01 ~]$ /usr/local/bin/MyBlaster.pl 298
>>>> Does change the channel.
>>>>
>>>> Anyone have any thoughts?
>>>>
>>>> Thanks!
>>>>    
>>>>         
>>> Probably the most common problem with scripts is that they have be  
>>> both readable and executable in order to work. Just a simple thing to  
>>> check.
>>>  
>>>       
>> chmod +0777 /usr/local/bin/MyBlaster.pl
>> chmod +x /usr/local/bin/MyBlaster.pl
>>     
>
> They don't, however, have to be world writable and it's bad practice -- 
> even on a dedicated system on a safe LAN -- to make things world 
> writable.  0755 maybe, but not 0777.
>
> Are you running your command line test (which works) as the same user 
> that mythbackend is running?  This script will have to access some 
> device, which will also have permission issues if mythbackend isn't 
> running as root.
>
> Beware also if you're running mythbackend as setid root: perl may see 
> that real-user != effective user and try to run a taint-controlled 
> version.  That can be tricky to get working.
>
> Len
>   
To be honest I have no idea what user the mythbackend is running as, I
followed Jarod's guide substituting FC4 with CentOS (RHEL4). Is there a
way to find this out?

-Kenneth