1 //

     2 //    readme.txt - introduction to the CGI library

     3 //

     4 //    Portions Copyright (c) Symbian Software Ltd. 2007.

     5 //    Portions Copyright (C) 1999-2004 Nokia. * Nokia Core OS *

     6 //    Save as expressly licensed to you by Symbian Software Ltd, all rights reserved.

     7 //

     8 ////////////////////////////////////////////////////////////////

     9 // WS_CGI.DLL

    10 // Deriving a DLL from CExecCGI

    11 

    12 CExecCGI is an abstract class, inteded for derivation in a polymorphic interface DLL. This abstract class has some

    13 static functions which are implemented in a static interface DLL. When the polymorphic interface DLL is loaded

    14 any static interface DLL requiered by the polymorphic DLL are also loaded. So you do not have to worry about this.

    15 

    16 Mainly, the CGI programmer has only to implement the pure virtual function ExecCGI(). The enviroment variables are

    17 defined as a class (TCgiEnv). The command-line arguments are also implented as a class (CCommandArg). Their values are set by the 

    18 WebServer.

    19 

    20 The communication with the webserver is done through two functions: Read and Write.

    21 (*) TInt Read(TDes& aBuffer)

    22 

    23 Note: This functions reads data from the WebServer.

    24 

    25 Arguments

    26 =========

    27 

    28 TDes& aBuffer

    29 -------------

    30 Descriptor into which characters are read. Any existing contents are overwritten. 

    31 On return, its length is set to the number of characters read. The length is set to zero when there are no more

    32 characters to be read.

    33 

    34 

    35 Return

    36 ======

    37 

    38 TInt

    39 ----

    40 An error code.

    41 

    42 (*) TInt Write(TDesC& aBuffer)

    43 

    44 Note: This functions sends data to the webserver.

    45 

    46 Arguments

    47 =========

    48 Descriptor from which characters are written.

    49 

    50 Return

    51 ======

    52 

    53 TInt

    54 ----

    55 An error code.