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Since then he has also worked on a number of OBEX projects,as well as a smaller number of Bluetooth projects – the main one beingpart of the initial implementation of Bluetooth PAN profile. He is currentlyfocusing on USB, but frequently supports maintenance work on IrDA andOBEX. Out of work hours, Ian is a keen photographer, and also makesitems of jewellery.Lucy CafferyLucy has been at Symbian since 2000, where she has worked for theLicensee Product Development team helping UIQ licensees to createSymbian products. Starting out as a Bluetooth specialist, she becameHead of the Comms Porting group in LPD, a team which specializes inconsultancy in all areas of the Symbian OS Comms subsystem.

Morerecently Lucy has become the Deputy Head of LPD. Lucy has beeninvolved in comms on all the UIQ devices that have shipped to date:Sony Ericsson P8xx, P9xx, M600i, W950i and P990, Motorola A92x,A1000 and M1000.Pierre CochartPierre Cochart graduated from King’s College London in 2000.

He thenjoined Symbian as a graduate in the telephony team to help with thedevelopment of the 7.0 OS release. In 2003 he joined Licensee ProductDevelopment group to work in the Comms Porting group where heassisted customers with software development in various areas of comms.Pierre is now responsible for handling the communications area for theJapanese licensees.Twm DaviesTwm joined Symbian as a graduate in 1999. Twm has had a varied careerwithin Symbian, initially working as a developer of the ’crystal’ messagingapplication which provided the UI to the Nokia communicator range,then as a technical consultant for Motorola, Nokia and significantly thetechnical lead on the first non-Nokia S60 handset, the Siemens SX1.

Twmcurrently works as Product Manager for performance. Twm graduatedABOUT THE AUTHORSxiiifrom Cardiff University with a First Honours Computer Science BSc.Interests outside of work include collecting mispronunciations of hisname, scuba diving, Vespas and he runs a web site selling his art works.Matt ElliottMatt joined Symbian in 2004 as a software engineer, and has spent histime at Symbian in the Device Provisioning team. He graduated with aBEng in Digital Electronics from the University of Kent, and coming froma hardware background still misses his soldering iron (but not the burntfingers). Matt would like to thank all the past and present members of theDevice Provisioning team for their carefully worded criticism/help, andhis long suffering girlfriend Elaine.Natasha HoNatasha joined Symbian in 1998, where she worked on the developmentof the Ericsson R380.

Since then, she has contributed to almost every UIQsmartphone including the Motorola A920 and A1000, the Arima U300and more recently the Sony Ericsson P800, P900, M600i, W950i andP990i. She has worked on various parts of the Symbian OS but now likesto concentrate solely on networking. Prior to Symbian, Natasha worked atMotorola designing and writing software for the GSM and GPRS cellularinfrastructures. Natasha graduated from University College London witha BSc in Computer Science.Emlyn HowellEmlyn Howell has worked on various technologies within Symbian overthe past seven years including messaging and telephony. He is currentlythe Comms Architect for the Reference Designs team.

He lives and worksin Cambridge.Tim HowesAfter studying for a PhD in the effects of indirect lightning strikes onpower lines, Tim joined Symbian Software, where for seven years he hasworked primarily within the Bluetooth area. Within the Bluetooth SIG,Tim represents Symbian on the Bluetooth Architecture Review Board, andcontributes to the Core Specification, Audio Video and Medical DevicesWorking groups. Despite the high technology area Tim works in, he hasa strong interest in mechanical timepieces.xivABOUT THE AUTHORSIbrahim RahmanIbrahim has been at Symbian for eight years.

Working as a softwaredeveloper in areas including email and HTTP.Dale SelfDale started work for Psion Software in mid-1998, which transformed toSymbian about a week later. Initially working in the messaging team onan IMAP4 mail client, he later moved to the PAN team where he hasworked with Bluetooth, OBEX and USB technologies ever since. Duringthis time he has seen a great deal of growth; both in Symbian, and, sadly,in his waist measurement.AcknowledgementsFirstly we’d like to thank the Symbian Press team who helped put thisbook together, especially Satu, who kept us working on it until it wasfinished – without her it would probably be sitting half-written on varioushard disks around Symbian.Secondly we’d like to thank all of our wives, husbands, partners andsignificant others for putting up with us whilst we hid away in the eveningsand weekends writing the material for this book.I’d like to thank Apple for creating a computer that’s a pleasure touse – it made the whole editing process so much less painful.And finally I’d like to extend an additional thank you to my wife Chris,who put up with me not moving from in front of the computer for a monthwhilst I pulled the book into shape.Iain CampbellSymbian Press AcknowledgementsSymbian Press would like to thank Iain for his patience during this projectand for the countless hours he spent polishing the text into perfection.We’d also like to thank the authors Dale, Emlyn, Ian, Ibrahim, Lucy,Malcolm, Matt, Natasha, Pierre, Tim and Twm for their dedication andhard work, and all the reviewers for their time and willingness to sharetheir technical knowledge.Section IIntroduction and Overview1IntroductionWelcome to the updated edition of Symbian OS CommunicationsProgramming! In this book we’ll introduce you to much of the majorcommunications functionality in Symbian OS and demonstrate how toperform common tasks in each area.For this new edition we’ve started from scratch to produce chaptersthat are relevant to you as developers.

Each chapter gives backgroundinformation on the technology where necessary, an overview of thefunctionality provided in Symbian OS, and descriptions or examples ofhow to use the Symbian OS APIs. In cases where APIs or implementationdiffer between Symbian OS-based devices this is noted, and when theuser interface platforms work differently then we’ll show you whatthose differences are, or at least point you in the direction of somedocumentation that does.1.1 What is in this BookIn this book we focus on using and extending Symbian OS functionalityusing the native C++ APIs.

Whilst it is also possible to use Java todevelop applications for Symbian OS devices, we do not cover that inthis book. We also focus on APIs available in standard UIQ3 and S60 3rdedition SDKs – thus engineers at Symbian’s licensees and partners willwant to look elsewhere for details on the internals of the Symbian OSsubsystems that we describe. However, the material in this book is suitedto all developers – at third parties, Symbian’s licensees and Symbian’spartners – who wish to use the functionality described.This book should also prove useful to newcomers to Symbian OSin the device creation community, providing a high-level overview ofthe communications side of Symbian OS, and an idea of how it all fitstogether. However, this is not likely to be sufficient for creating a device,for that you will need to look elsewhere.4INTRODUCTIONThere are three main user interfaces supported on Symbian OS –MOAP, S60 and UIQ.

At present, only S60 and UIQ allow developersto extend functionality natively in the aftermarket, so we concentrate onthose platforms in this book.S60 and UIQ have, in some places, differences in the way they chooseto use and expose certain Symbian OS functionality. As a result, somedetails given in this book differ between the different UI platforms. Wherethis is the case we will highlight this, along with tips on how to use thefunctionality on each platform.

In some cases functionality might havean alternate implementation on a given platform, in which case we willpoint you to the appropriate developer documentation. In other cases,it might be missing entirely, which might mean you need to reconsideryour development plans. In cases where functionality is missing or notyet exposed, it is possible that it will be available in a later release ofthat UI platform – check with the appropriate developer website for moreinformation in these cases.The scope of this book is quite broad – not only will we discuss thecore communications functionality in Symbian OS – Bluetooth“, IrDA,TCP/IP and telephony, but we also look at some of the main areaswhere those technologies are employed – the messaging framework andplug-ins, the HTTP stack, the OBject EXchange (OBEX) stack and theOMA Device Management system. Therefore whether you need accessto communications functionality at a high or a low level, there should besomething in this book for you.1.2 What isn’t in this BookSymbian’s licensees have a lot of flexibility when creating a device – asis necessary in a market where there is plenty of differentiation betweenproducts.

As such, the supported feature set in any given device dependsgreatly on the market segment at which that device is aimed. Youcan expect to find that some features are not supported in givendevices – either where they are not suitable, or cost-effective enoughto be included.Equally, some devices have leading-edge features that have beendeveloped for differentiation – in these cases, the generic implementation developed when the feature becomes widely available may differfrom the original one, which is normally highly tailored for the leaddevice.

Throughout this book we describe the generic implementations – the ones you can rely upon to remain compatible beyond theinitial implementation. Therefore it is best to use these implementationswherever possible to minimize, or eliminate, the amount of rework yourapplication requires when deploying it to a new device.WHAT ISN’T IN THIS BOOK5However, you may wish to use some of those leading-edge features,perhaps because your application is targeted specifically at the devicecontaining them.

In that case, we advise you to go directly to thedevice manufacturer’s developer website for information on using suchfeatures.1.2.1 Technologies not Covered in this BookThere are some notable absences from this book in terms of technologiesthat Symbian OS supports. The reasons for their omission vary, but belowwe’ll summarize the main technologies that are missing.USBSymbian OS has included support for acting as a USB device (or client)since Symbian OS v7.0, and this support was backported to v6.1 forcertain devices.

However, extending this support is difficult due to thenature of the USB controllers used in devices. Typically these have alimited number of USB endpoints. By the time most devices are shipped,their USB configuration is such that most, if not all, of those endpointsare in use. This means that third-party extensions would not be possible,as they would not have any resources available with which to implementtheir functionality. As a result, Symbian defines the APIs required toextend the USB implementation as partner-only.The one case where USB functionality might be of use to developersis the USB virtual serial port (more accurately, the USB ACM class).However, current devices are rarely configured to leave an availablevirtual serial port – in most cases they are already in use, providing theinterface to use the device as a modem, or for use with debug agents.Check the documentation for the devices you are targeting to see if thereis a USB serial port available – if there is, then it can be accessed via theRComm interface.1Real-time protocol and real-time control protocol (RTP and RTCP)The Symbian OS implementation of RTP has been supported sinceSymbian OS v8.1, and has been shipping in devices since v9.1.