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  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-9D871368-ADB9-5588-A1F3-39A432F4F32E" xml:lang="en"><title>Command
Line Parsing </title><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>Command Line Parsing provides access to arguments passed on the command-line. </p>
<p>Conventional C and C++ programs receive their arguments from <codeph>main(
        int argc, char* argv[] )</codeph>. On the Symbian platform,
programs are invoked through an <codeph>E32Main()</codeph> function taking
no arguments. Most Symbian programs are launched through a graphical shell
rather than through a command-line. The common exceptions are <filepath>.exe</filepath> s
on the PC platform, which can be run from a Windows command prompt. </p>
<p>For <filepath>.exe</filepath> programs, control is received through the <codeph>E32Main()</codeph> function,
which does not supply arguments. Instead, access to arguments is provided
by <xref href="GUID-CE114EA5-A084-39A5-9F48-14344AB5BDBA.dita"><apiname>CCommandLineArguments</apiname></xref>. This class is not intended primarily
for code running on a Symbian phone. Its main use is in parsing the arguments
of WINC command-line utilities. </p>
<p>For a program that is launched as a new process, the arguments are available
as part of the process command line and may be obtained in full using code
as the following: </p>
<codeblock id="GUID-CA0EBC3E-1FB5-5E39-8790-DE3131DB1B77" xml:space="preserve">TInt argLen = User::CommandLineLength();
HBufC16* hBuf = HBufC::NewL( argLen );
TPtr tPtr = hBuf-&gt;Des();
User::CommandLine( tPtr );</codeblock>
<p>However, the arguments are in a raw form. For convenience, the <codeph>CCommandLineArguments</codeph> class
provides functions to access the program name as argument 0, and each command-line
argument as argument 1, 2 etc. Arguments beginning with a quote may contain
blanks and doubled quotes. Arguments not beginning with a quote are terminated
by a blank. </p>
</conbody></concept>