SysV IPC

[LeoTh3o]

I have been trying recently to revive my project to port PostgreSQL to iOS.

Please note that there hasn't been problems in the building itself, just a great amount of bad system calls at runtime.

I did some search and found this:http://postgresql.1045698.n5.nabble.com/Postgresql-iPhone-td3958621.html
it would kind of surprise me if Apple had bothered to support
SysV IPC primitives in iOS.  You'd need to find replacements for our
sysv_shmem and sysv_sema modules.  It's possible that posix_sema would
work, although I'd bet against that too.

In fact, Apple has not implemented either, but has happily put headers such as sys/ipc.h and sys/shm.h in the SDK.

The sample test from http://www.ibm.com/developerworks/aix/library/au-ipc/ actually proves this:

My key is -1
Bad system call: 12

Sysctl also says so:
kern.sysv: No such file or directory


I'll be looking for a solution or an already existing implementation of SysV

[grinch]

Keep up the good work sir! Having PostgreSQL on iOS would be HUGE

Sorry I can't help with this issue

[LeoTh3o]

After a day surfing the net, I humbly admit defeat. There seem to be no implementation of sysv except the one from libffi for iOS. Due my scarce comprehension of assembly, I cannot say what is done there and wouldn't be able to replicate it, anyway.

I do lack specific knowledge of what actually sysv does and how can implemented in a system not providing it by default. To solve it in an elegant way there should be someone either experienced in system programming and/or someone able to disclose some of Apple's internal stuff. I don't happen to know any of this kind of person.

As a last attempt, I'll try to make configure NOT find headers for SysV and see what happens.

I'd be interested if any other member of ininjas can provide better insight of the problem and/or figured something more out.

As a last note, I think that APR rely on SysV, which would explain why it's not possible to build a working one.

[LankAsif]

I am a lil off topic here, but just wanted to say that even though I know diddly about this kinda thing, your posts were a pleasure to read LeoTh3o. Thank you for taking the time to share your findings. It is a thread like this that inspires me to learn more.
I wish ya luck comrade