Semaphores in eldk4.1

Wolfgang Denk wd at
Sat Dec 1 09:27:26 EST 2007

In message <47503B5A.6090604 at> you wrote:
> I have been suing the eldk4.1 tool chain for a few months now and have 

Please post ELDK related questions on the ELDK mailing list instead,

> The problem I have come up against is related to some of the semaphore 
> functions in semaphore.h, namely sem_wait, sem_post. This was originally 
> noticed in a third party driver I am porting from one board to another 
> but a small test program has shown the same results.

What exactly are you talking about? Device driver (i. e. kernel)
code, or application (i. e. user space) code ?

> Calls to these functions on the ppc_82xx platform return -1 with an 
> error code of 38, in this case meaning  ENOSYS (not implemented). On the 

Did you enable the CONFIG_SYSVIPC option in your Linux kernel

> ppc_85xx the same program executes fine, thus I conclude that it is 
> specific to the libc-2.3.5 for ppc_82xx. Has anyone else come across 
> this problem, I did find one thread but there was no conclusion listed.

There is absolutley no difference between ppc_85xx and ppc_82xx as
far as library sources or configuration are concerned. The problem is
most probably in your Linux kernel, I guess.

> I also can not find anything stating that these functions are not 
> implemented for the 82xx arch compared with others for the eldk4.1

Provide a test program that fails for yuou, and we can provide much
better comments.

But please post followups on the ELDK mailing list.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at
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