could not mmap /dev/dsp

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could not mmap /dev/dsp

Postby LoRd_CJ » Sun Nov 20, 2005 1:27 pm

Another problem, trying to start wolfenstein: enemy territory with sound and I get:

/dev/dsp: Invalid argument
Could not mmap /dev/dsp

Again, latest drivers and FreeBSD 6.

Also, I had an issue with permission denied to all device nodes right after installing OSS. I had to chmod 666 /dev/dsp* and /dev/mixer*

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Joined: Fri Jun 11, 2004 1:50 pm

Postby adamk » Thu Aug 27, 2009 12:21 pm

FYI, I am also getting the same error with Return to Castle Wolfenstein and OSS4.2 on both a soundblaster live and ich.


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Joined: Sun Aug 12, 2007 12:51 am

Postby cesium » Thu Aug 27, 2009 9:28 pm

I wish you didn't resurrect a 4 year old thread...

Anyway, the problem is that the per-fd data storing api (cdev_set_priv() or something like that) is mostly incompatible with mmap()**, so OSSv4 can't do mmap() unless the per-fd code is disabled (i.e. OSSv4 is recompiled with VDEV_SUPPORT undefined. One would have to edit kernel/OS/FreeBSD/wrapper/bsddef.h to do this properly). This would have the effect of preventing vmix from being able to get multiple clients on /dev/dsp...

** IIRC, they did a sort-of an hack where it works only for a certain type of accesses...

*** The permissions issue in the original post is probably due to some crazy umask? Latest OSS clears umask before creating the nodes.

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