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<DIV dir=ltr><FONT face="Courier New" color=#000000 size=2>Hi
Surindar,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>I am not sure of what you
refer to as there being a reference</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>to a supervisor in for
instance gen_server:start_link, but non</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>in gen_event:start_link. There is
infact no reference to the</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>supervisor in gen_server:start_link
either. The relationship</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>between the supervisor and its
newly created child process is</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>established by the gen_server or
gen_event code automatically.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>And of course the fact that a
client function calling the</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>start_link function is called from
the the supervisor in</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>questions. A supervisor is made to
call the clientfunction</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>starting the new child by placing
it in its children specification.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Have you taken a look at
the Working with OTP chapters in</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>the online documentation? There is
for instance an example on</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>how to start an event-manager
process using gen_event.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2><A
href="http://www.erlang.org/doc/doc-5.4.12/doc/design_principles/part_frame.html">http://www.erlang.org/doc/doc-5.4.12/doc/design_principles/part_frame.html</A></FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Best Regards,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Lennart</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" color=#000000
size=2></FONT> </DIV></DIV>
<DIV id=idSignature2187 dir=ltr>
<DIV><FONT face="Courier New" color=#000000
size=2>-------------------------------------------------------------</FONT></DIV>
<DIV><FONT face="Courier New" color=#000000 size=2>Lennart
Ohman
phone : +46-8-587 623 27</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sjöland & Thyselius Telecom
AB cellular: +46-70-552 6735</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sehlstedtsgatan
6
fax : +46-8-667 8230</FONT></DIV>
<DIV><FONT face="Courier New" size=2>SE-115 28 STOCKHOLM,
SWEDEN email : <A
href="mailto:lennart.ohman@st.se">lennart.ohman@st.se</A></FONT></DIV></DIV>
<DIV dir=ltr><BR>
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<FONT face=Tahoma size=2><B>Från:</B> owner-erlang-questions@erlang.org genom
Surindar Sivanesan<BR><B>Skickat:</B> to 2006-03-02 13:56<BR><B>Till:</B>
erlang-questions@erlang.org<BR><B>Ämne:</B> OTP tree doubts<BR></FONT><BR></DIV>
<DIV>
<DIV>Hi all,</DIV>
<DIV> </DIV>
<DIV>I have some doubts in OTP design.</DIV>
<DIV> </DIV>
<DIV>1.In gen_event behaviour, it is mentioned in the document that,
start_link() function creates an event manager process as part of a supervision
tree.But in that function there is no parameter of supervisor reference. In case
of gen_server or gen_fsm behaviour, the start_link function has the supervisor
reference as parameter. I'm able to understand gen_fsm and gen_server but
gen_event is still confusing. If there is any example applying gen_event, please
give me. </DIV>
<DIV> </DIV>
<DIV>2.I can create a thread which continuously running in a loop</DIV>
<DIV> </DIV>
<DIV>ex:</DIV>
<DIV>-module(sample).</DIV>
<DIV> </DIV>
<DIV>start()-></DIV>
<DIV>spawn(sample,continuous,[]).</DIV>
<DIV><BR clear=all>continuous()-></DIV>
<DIV>%%Functionality is done here</DIV>
<DIV>continuous().</DIV>
<DIV> </DIV>
<DIV>whether the same type of thread is implemented as child like gen_fsm,
gen_server, gen_event in OTP tree.</DIV>
<DIV> </DIV>
<DIV>Please clarify me<BR>-- <BR>with regards,<BR>S.Surindar
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