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Posix semaphores

Hello,

I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.

I have not seen it defined in the posix specification I have found, but
I have maybe missed something.

Thanks in advance.

FiLH

--
Le fondement du constat bourgeois, c'est le bon sens, c'est-à-dire
une vérité qui s'arrête sur l'ordre arbitraire de celui qui la parle.
Roland Barthes.
http://www.filh.org
Nov 15 '05 #1
11 3016
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3r924.rm wehsgf97rrN%fi* *@filh.orgie...
I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.


This is beyond the scope ot the C programming language with which this group
deals. Try posix/unix-related group instead.

Alex
Nov 15 '05 #2
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3r924.rm wehsgf97rrN%fi* *@filh.orgie...
I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.


This is beyond the scope ot the C programming language with which this group
deals. Try posix/unix-related group instead.


Which one dear ?

FiLH

--
Le fondement du constat bourgeois, c'est le bon sens, c'est-à-dire
une vérité qui s'arrête sur l'ordre arbitraire de celui qui la parle.
Roland Barthes.
http://www.filh.org
Nov 15 '05 #3
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3rce9.uk 3bam6uzytjN%fi* *@filh.orgie...
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3r924.rm wehsgf97rrN%fi* *@filh.orgie...
I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.


This is beyond the scope ot the C programming language with which this group deals. Try posix/unix-related group instead.


Which one dear ?


Not this one, that's for sure. Try searching through
http://groups.google.com.

Alex
Nov 15 '05 #4
fi**@filh.orgie (FiLH) writes:
I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.

I have not seen it defined in the posix specification I have found, but
I have maybe missed something.


Try comp.unix.progr ammer.

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.
Nov 15 '05 #5
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3rce9.uk 3bam6uzytjN%fi* *@filh.orgie...
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3r924.rm wehsgf97rrN%fi* *@filh.orgie...
> I would like to know if posix semaphores are inter processes or just
> semaphores for threads inside the same process.

This is beyond the scope ot the C programming language with which this group deals. Try posix/unix-related group instead.


Which one dear ?


Not this one, that's for sure. Try searching through


So, you are juste speaking about forums that you don't even know if they
exist ?

Hum... do you have any valuable information ?

Or you are just one of theese wanabee cop that is trying to get some ego
boost ?

Btw I don't really understand why the C forum is not a place to discuss
about the C normalized libraries.

FiLH

P.S. THere is no posix dedicated group, I checked before posting here.

--
Le fondement du constat bourgeois, c'est le bon sens, c'est-à-dire
une vérité qui s'arrête sur l'ordre arbitraire de celui qui la parle.
Roland Barthes.
http://www.filh.org
Nov 15 '05 #6
Keith Thompson <ks***@mib.or g> wrote:
fi**@filh.orgie (FiLH) writes:
I would like to know if posix semaphores are inter processes or just
semaphores for threads inside the same process.

I have not seen it defined in the posix specification I have found, but
I have maybe missed something.


Try comp.unix.progr ammer.


Thanks.

FiLH
--
Le fondement du constat bourgeois, c'est le bon sens, c'est-à-dire
une vérité qui s'arrête sur l'ordre arbitraire de celui qui la parle.
Roland Barthes.
http://www.filh.org
Nov 15 '05 #7
fi**@filh.orgie (FiLH) writes:
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3rce9.uk 3bam6uzytjN%fi* *@filh.orgie...
> Alexei A. Frounze <al*****@chat.r u> wrote:
> > "FiLH" <fi**@filh.orgi e> wrote in message
> > news:1h3r924.rm wehsgf97rrN%fi* *@filh.orgie...
> > > I would like to know if posix semaphores are inter processes or just
> > > semaphores for threads inside the same process.
> >
> > This is beyond the scope ot the C programming language with
> > which this group deals. Try posix/unix-related group instead.
>
> Which one dear ?
Not this one, that's for sure. Try searching through


So, you are juste speaking about forums that you don't even know if they
exist ?

Hum... do you have any valuable information ?

Or you are just one of theese wanabee cop that is trying to get some ego
boost ?

Btw I don't really understand why the C forum is not a place to discuss
about the C normalized libraries.


I don't know what you mean by "C normalized libraries", but the C
standard does not support semaphores, threads, or processes. POSIX is
a separate standard.

Not everyone here can be expected to know about all the other
newsgroups where a question might be topical.

When we tell people that certain things are off-topic here, it's not
because we're "wanabee cops". It's because standard C is the area we
know about, and there are other newsgroups for more system-specific
topics where you're more likely to get good answers (and those answers
are more likely to be checked for accuracy by other experts).
P.S. THere is no posix dedicated group, I checked before posting here.


Alexei suggested a "posix/unix-related group". I see at least 56
newsgroups with "unix" in their names. Of them, comp.unix.progr ammer
is probably the best for your purposes. comp.programmin g.threads is
another good possibility. You should browse the archives of both
groups, and read their FAQs if you can find them, before posting.

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.
Nov 15 '05 #8
FiLH wrote:
Alexei A. Frounze <al*****@chat.r u> wrote:
"FiLH" <fi**@filh.orgi e> wrote in message
news:1h3rce9. uk3bam6uzytjN%f i**@filh.orgie. ..
Alexei A. Frounze <al*****@chat.r u> wrote:
<snip>
deals. Try posix/unix-related group instead.

Which one dear ?
Not this one, that's for sure. Try searching through


So, you are juste speaking about forums that you don't even know if they
exist ?


He probably know that they exist but he might not know the names of them.
Hum... do you have any valuable information ?
That this is the wrong group is valuable information. He also suggested
unix groups which you obviously had not thought of looking for so that
was also valuable information which you have chosen to ignore.
Or you are just one of theese wanabee cop that is trying to get some ego
boost ?
No, he is trying to keep the group useful by keeping it topical.
Btw I don't really understand why the C forum is not a place to discuss
about the C normalized libraries.
They are not C libraries, they are POSIX libraries.
FiLH

P.S. THere is no posix dedicated group, I checked before posting here.


There are, however, plenty of Unix groups, both generic ones such as
comp.unix.progr ammer and ones dedicated to specific Unix variants. There
is also comp.programmin g which would probably have been a better place
to start given that you could not find the correct group.
--
Flash Gordon
Living in interesting times.
Although my email address says spam, it is real and I read it.
Nov 15 '05 #9
Hi group!!
Well i would like to just say that don't just stop replying if the
answer is known by somebody in the group.
As far as i know the POSIX and MUTEX threads are related to the
processes in the unix environment.Sep arate programs are written to
handle them.
Semaphores are just like FLAGS in the processes.They help to indicate
the switching of processes.
http://docs.sun.com/app/docs/doc/817...jum5sg7?a=view
they say it is interprocess

Nov 15 '05 #10

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