Download EMS Portable Workflow - Computer Science
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A collection of Net Library functions are used to give the desired functionality to these functions. Each of these Net Library functions is defined in NetMgr.h. 4.2.1.1 SendData The SendData function sends an XML string containing incident report information. It is the function that is called when a user wishes to send an incident report. To send the string, the Net Library must be opened so the NetLib function calls can be utilized. With the Net Library open, SendData can verify a host name and service name and make a socket connection to the server. At this point, data can be sent or received. When finished with all network transactions, the socket, as well as the Net Library, is closed, and the status of the transmission is returned. 4.2.1.1.1 Find/Open Net Library The Net Library must first be found using the SysLibFind system function before it can be opened. Err SysLibFind (const Char *nameP,UInt16 *refNumP) Function Return a reference number for a library that is already loaded, given its name. Purpose Parameters nameP – Pointer to the name of a loaded library. Result Called By refNumP - Pointer to a variable for returning the library reference number (on failure, this variable is undefined) 0 if no error; otherwise: sysErrLibNotFound (if the library is not yet loaded), or another error returned from the library's install entry point. This method is called from the SendData() function in EIRXMIT.c When the Net Library has been found, it is then opened by calling NetLibOpen. This call reads from the network configuration file on the handheld, making a physical connection to the wireless medium via one of WPI’s wireless access points. The function then loads the network protocol stack. Err NetLibOpen (UInt16 libRefnum, UInt16 *netIFErrsP) Function Opens and initializes the Net Library. Purpose Parameters libRefnum – Reference number to the Net Library. Result Called By netIFErrsP – First error encountered when bringing up network interfaces. 0 - if no error netErrAlreadyOpen – returned if library is already open netErrOutOfMemory – not enough memory available to open library. netErrNoInterfaces – incorrect setup. netErrPrefNotFound – incorrect setup. This method is called from the SendData() function in EIRXMIT.c 69