[GEM-dev] Re: pix_share broken several ways

[IOhannes m zmoelnig]

chris clepper wrote:
> On 6/7/06, *chris clepper* <cgclepper at gmail.com 
> <mailto:cgclepper at gmail.com>> wrote:
> 
> 
>     Finally, after setting up one shm buffer at an address I can no longer
>     create one at any other address.  I get this message:
> 
>     pix_share_*: 2048x768x2: 3145728
>     error: pix_share_*: couldn't get shm_id: error 12 
> 
> 
> pix_share_write might not be releasing the shm object correctly or at 
> all.  

you are right. in the process of detecting how big an already segment is 
attached a memory segment and did not properly release it anymore.

i have checked in a fix for this.

actually it is just an "shmdt(h);" below the "m_size=h->size;" below the 
"somebody was faster" warning.

> I could only get one set up for a ~2.5MB buffer without rebooting 
> to free up more.  OSX might have changed the shmmax defaults to 4MB 
> total in a recent update as well.  I put it to 8MB and can now use a 
> 1024x768x4 buffer after a fresh reboot although changing it to one 
> double that size using the set message fails.

note that you can only resize the buffer to something larger if nothing 
refers to this segment any more.

mfg.asdr.
IOhannes